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Thread: Ideal Bolt Action Rifle

  1. #61
    Boolit Grand Master Artful's Avatar
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    Quote Originally Posted by Ed in North Texas View Post
    But is the suppressor on a supersonic round worth the cost of the supressor + $200.00? Other than "cool factor", that is. That is only worth what the beholder believes. Or, through reloading, did you turn it into a low budget .300 Whisper rifle?
    Ed already owned the suppressor so no additional cost - and yes I use that can on 308 and 300 whisper with subsonic loadings making for real quiet shooting. Can I make up 7.62x54 reduced or subsonic ammo - you bet!

    Does it reduce the standard surplus ammo from flame throwing shock wave making explosions that drive people away from me on the shooting line
    to something that will make quiet enough so that Kurt quit grabbing his torso and saying "my aching liver" everytime I fired it - yep tamed it right down.

    Quote Originally Posted by Ed in North Texas View Post
    So you are saying that a .223 standard velocity round is effectively silenced by the suppressor? Or are you saying that the sound level at the firing point is reduced?

    I'm not quite sure what you are asking about the .22 lr, but I am aware that sub-sonic .22 lr is available, as well as sub-sonic 9mm specifically designed for suppressed weapons (e.g. MP-5 with suppressor and 147 gr sub-sonic ammo).

    I guess it may come down to what the individual expects from the suppressor, a "silenced" shot, reduced sound at the firing point, or something else.
    Does a supersonic round sound different suppressed - yep - that same 30 caliber can on my .243 will make the gun hearing safe (under 140 db) so if I forget to put in plugs or on muff's and shoot I don't have partner's deafened. Does it make it sound like subsonic - no way - I have also used on my AR15 and with the 30 caliber can in place it does sound like an unsuppressed 22LR HV instead of .223. Again hearing safe but not silent about 126-135 db. If your looking for silent the best your going to get is a 22LR with subsonic with a good suppressor - about 112-118 db depending upon host system.

    Oh, and yes sub-sonic ammo makes a huge difference but you have to be aware of trajectory difference the 22LR subsonic drops over 9 ft at 300 yards, so range estimation is key - and if you buy a MP5SD be aware that the barrel is bored out with 24 wee little holes to make 124 gr NATO std 9mm subsonic and if you use 147 subsonic in that weapon you've reduced the velocity to a point were it will bounce off a heavy coat (yes, this has happened).

    Would my M38 be an ideal rifle - I'd say it could be for someone with the right expectations - 7.62x54 is a round capable of killing human predator or up to Bear size Predator's would it stop a charging elephant maybe if you knew where to place the bullet - cast boolit friendly and subsonic capable. I don't think you can go too wrong with it as a choice. If I want a smoother action look for a krag, if you want 98 action bubba it until you get it - parts are out there. As far as safety of M38 it seems to do well with parent cartridge I have not heard of a lot of problems with it.
    Last edited by Artful; 10-05-2011 at 01:00 AM.

  2. #62
    Boolit Grand Master 303Guy's Avatar
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    If your looking for silent the best your going to get is a 22LR with subsonic with a good suppressor - about 112-118 db depending upon host system.
    I would describe a suppressed 22lr subsonic as being as noisy as the firing pin - that's it. However, bullet strike is another matter. A suppressed 223 does indeed sound like a 22lr. A suppressed 22lr high velocity, that is.

    I built a suppressor for a 22-250 and it made the gun sound like an unsuppressed 22lr. And this suppressor was tiny, adding a mere 2" to the overall length.

    But not all suppressors are made equal. Some bigger and more expensive models are simply noisier and heavier.

    Something to remember, a three decibel increase is double the sound pressure so reducing sound pressure from 140db to 120db is a massive reduction in muzzle blast.
    Last edited by 303Guy; 10-04-2011 at 10:10 PM.
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  3. #63
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    Ed in North Texas's Avatar
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    Artful - thanks for clearing up my misunderstanding. But (here's the big but), as an old gun bunny (artilleryman) from the days when the Army issued ear plugs (and thought that protected hearing on an M-110 pushing a 200 pound projectile 12 miles), any noise level approaching 140 db is definitely not safe for your hearing. It doesn't harm your hearing in a big way, right away. But the damage is cumulative.

    Oh yes, and I wouldn't even try to hit anything with even a regular .22 LR at 300 yards. Not even 200 yards. I know my limitations (which get greater the older I get).

    Everyone can do themselves a favor and always remember to wear "ears and eyes". You don't need to be like me and have to buy hearing aids (which don't do all that much good in situations where there is much background noise). Not that I would want the hearing aids covered, but health insurance and Medicare do not cover them. "Ears" now are much cheaper. I had to buy electronic "ears" so I could hear range commands when I was participating in club matches because I couldn't hear the commands (or whistles, horns, etc.) without the amplifier.

    And besides, you won't have to suffer your wife telling you that there isn't anything wrong with your hearing, you just don't pay attention to her.
    Last edited by Ed in North Texas; 10-05-2011 at 10:08 AM.

  4. #64
    Boolit Master
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    From what I've heard if a sniper uses a suppressor with a supersonic cartridge those near the victim being fired on and not themselves hit would hear the crack further down range and believe, for a few precious seconds at least, that the shooting came from the opposite direction.
    Sounds feasible.
    In any case any reduction in muzzle blast is a plus.

  5. #65
    Boolit Grand Master Artful's Avatar
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    Ed I concur that any noise level approaching 140 db is definitely not safe for your hearing.
    But that is the standard for impulse noise exposure of short duration.
    Sources of noise that can cause hearing loss include motorized equipment, firecrackers, and small firearms, all emitting sounds from 120 to 150 decibels as in impluse.
    Long or repeated exposure to sounds at or above 85 decibels can and will cause hearing loss.
    The louder the sound, the shorter the time period before noise induced hearing loss (NIHL) can occur.
    Sounds of less than 75 decibels, even after long exposure, are unlikely to cause hearing loss.

    But long term noise above 75 will damage your hearing, it doesn't harm your hearing in a big way, right away.
    But the damage is cumulative and irreversable and you should be wearing hearing protection.
    But the Standard for "hearing Safe" short duration impulse noises are set as 140 db for impulse noise by the agencies involved.
    Any Suppressor that changes the pressure level to below 140 db "can" be considered as "safe".
    Of course the more reduction the better. And I know a lot of people who shoot thinking 22 rimfire etc. are save and they are not.

    For people who have not been exposed to the Logarithmic scale of sound measurement let me post some classic's
    0 db - Threshold of hearing - Don’t hear anything sound proof room
    10 db - Broadcast studio interior or rustling leaves - 1/32nd as loud as conversation
    20 db - Quiet house interior or rural nighttime - 1/16th as loud
    30 db - Quiet office interior or watch ticking - 1/8th as loud
    40 db - Quiet rural area or small theater - 1/4th as loud (and what our ears enviromentally were developed for)
    50 db - Quiet suburban area or dishwasher in next room - 1/2 as loud
    60 db - Office interior or ordinary conversation between two people in quiet environment - Ordinary Conversation
    70 db - Vacuum cleaner at 10 feet away from you - Twice as loud
    NOTE - hearing damage by continuous levels can start above 75 db
    80 db - Passing car at 10 ft. or garbage disposal at 3 ft - 4 times as loud
    90 db - Passing bus or truck at 10 ft. or food blender at 3 feet. - 8 times as loud
    100 db - Passing subway train at 10 feet or gas lawn mower at 3 ft. - 16 times as loud
    110 db - Night club with band playing or Chainsaw, 1 meter distance- 32 times as loud
    120 db - Threshold of pain instant pain ringing of ears- 64 times as loud as conversation (twice as loud as night club)
    140 db - Jet aircraft, 50 meter away
    ref'd links
    http://www.nidcd.nih.gov/health/hear...ges/noise.aspx
    http://trace.wisc.edu/docs/2004-About-dB/
    http://www.sengpielaudio.com/TableOf...sureLevels.htm

    Some measurements of real world sounds measured @ http://www.silencerresearch.com/deci...ce_library.htm

    Daisy Red Ryder BB Gun 94dB to 98dB
    Ruger 10/22 Hammer Falling on an Empty Chamber 102-103.5dB
    Ruger 10/22 Bolt Drop on an Empty Chamber 112-113dB
    Browning Buckmark Hammer Falling on an Empty Chamber 107-110dB
    Browning Buckmark Bolt Drop on an Empty Chamber 112-112.5dB
    Colt AR15 635 Style Upper Bolt Drop on empty chamber 114-119dB
    Black Maxx Paintball Gun shot with paintball 116.5dB to 119dB
    Black Maxx Paintball Gun shot without paintballs 126dB
    Mossberg 44US Target Rifle 26" Barrel CCI Subsonics 128dB to 129.5dB
    Mossberg 44US Target Rifle 26" Barrel CCI CB Longs 121.7dB
    Mossberg 44US Target Rifle 26" Barrel Remington Subsonics 129dB to 131dB
    All these measurements were done with Mil-spec sound meter 1 meter from object being measured.
    Last edited by Artful; 10-05-2011 at 11:56 PM.

  6. #66
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    SO STANDING NEXT TO AN A-4, A-6, F-4 or AV8A WHILE THEY WERE RUNNING UP THE ENGINES PROBABLY WASN'T A GOOD IDEA? WHAT'S THAT YA SAY??? SORRY, I DIDN'T CATCH THAT. WHAT???

  7. #67
    Boolit Master
    Ed in North Texas's Avatar
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    Quote Originally Posted by Bret4207 View Post
    SO STANDING NEXT TO AN A-4, A-6, F-4 or AV8A WHILE THEY WERE RUNNING UP THE ENGINES PROBABLY WASN'T A GOOD IDEA? WHAT'S THAT YA SAY??? SORRY, I DIDN'T CATCH THAT. WHAT???
    In fact I remember that the Army belatedly decided that the noise level of the Gas Turbine Generator Set (GTGS) of the Sergeant Missile System equipment was damaging crew members hearing, and that noise level was nowhere near what the aircraft engines turn out.

  8. #68
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    Sorry about going off track here, but you guys that have an FR8, do you use 7.62 NATO or commercial 308 Winchester ammo in it. I bought one of those FR8's about a month ago, will they hold up to the easier to find 308 win. ammo? I'm not worried about handloading for it right now.
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  9. #69
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    Quote Originally Posted by Trey45 View Post
    Sorry about going off track here, but you guys that have an FR8, do you use 7.62 NATO or commercial 308 Winchester ammo in it. I bought one of those FR8's about a month ago, will they hold up to the easier to find 308 win. ammo? I'm not worried about handloading for it right now.
    I have only shot ammo that is .308 spec and of course a bunch of cast loads too.
    You can miss fast & you can miss a lot, but only hits count.

  10. #70
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    Quote Originally Posted by Trey45 View Post
    Sorry about going off track here, but you guys that have an FR8, do you use 7.62 NATO or commercial 308 Winchester ammo in it. I bought one of those FR8's about a month ago, will they hold up to the easier to find 308 win. ammo? I'm not worried about handloading for it right now.
    Either is fine as the FR8 is the M98 action. Having pressure tested mumerous 7.62 NATO (foreign and domestic) cartridges and commercial .308W cartridges there's not really much real difference between them. Some 7.62 produce more psi than some commercial .308W and visa versa. I've no qualms about shooting any commercial .308W in my FR8.

    Larry Gibson

  11. #71
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    Thanks Larry, that's good enough for me. My only real concerns were the pressure differences, your testing alleviates my concerns. Looks like commercial 308 Winchester will be the FR8's diet until I start reloading for it.
    Give us this day our daily lead.

    Sic Semper Tyrannis.

    If you don't want 1984 you're going to need some 1776.
    WWGWD

  12. #72
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    FWIW Trey, I had my first and only double charge in ny FR8- 26.0 Red Dot behind an RCBS 30-180FN. Someone estimated the pressure at over 70K. I dunno, but a 98 Mauser made with good quality materials is a 98 Mauser made with good quality materials, ie- no worries.

  13. #73
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    Bret, thankfully your FR8 was built tough and you've got the fingers to prove it. That is indeed a testament to the durability of these rifles, however, I don't think I'll be trying that one myself!

    I imagine that was quite the eye opener, shooting a nice string of mild recoiling loads when suddenly you get a double charge. Glad you're ok.
    Give us this day our daily lead.

    Sic Semper Tyrannis.

    If you don't want 1984 you're going to need some 1776.
    WWGWD

  14. #74
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    All this talk of the FR8 caused me to get mine out and try some 185gr. Lee 312-185 sized to .309 with a GC. Loaded over 20gr. 2400 at 2.710. Shot pretty tight, but low. Kick wasn't bad, I think the steel recoil pad helped mitigate some of the recoil.....
    You can miss fast & you can miss a lot, but only hits count.

  15. #75
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    Quote Originally Posted by Three44s View Post
    I have an M38 amoung other Russians and it's my favorite of that series.

    Take a look at this before you give up on your M38:


    http://www.gswagner.com/mosin-nagant/safe/safe.html


    Wagner's home page:


    http://www.gswagner.com/

    If you need help climbing back out of there ..... PM me and I'll throw you a line!!! LOL!



    Enjoy

    Three 44s

    I made a similar but better one, a smaller 'ring' ( the 'u' shaped pc. from a lock) with cocking pc. drilled like your example and the 'u' welded on from the back....to which I attached a large split ring to pull on. I could remove the split ring and you hardly noticed the modification. Very neat and clean looking.

    I've read the Mosin action lacks a gas diversion port in case of ruptured case or primer.
    Just a personal feeling, but it just doesn't give me the confidence of a Mauser '98 action.

    But the Mosin carbines handle great, and the sights far better than a Mauser.
    I wouldn't turn one down if a good deal, I'd snap it up in a heartbeat. I'm looking at a possible buy of a 91/59 right now - if it's still there
    Last edited by Rio Grande; 10-13-2011 at 01:32 PM.

  16. #76
    Boolit Master NHlever's Avatar
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    Hmm,
    I've read this whole thread thinking that the FR-8 was the converted Spanish M93 actioned .308 Winchester like one I had years ago. What did I have? It fit the physical description you are talking about here, but was not a model 98 mauser!

  17. #77
    Boolit Grand Master Artful's Avatar
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    Quote Originally Posted by NHlever View Post
    Hmm,
    I've read this whole thread thinking that the FR-8 was the converted Spanish M93 actioned .308 Winchester like one I had years ago. What did I have? It fit the physical description you are talking about here, but was not a model 98 mauser!
    Sounds like you had FR-7

    FR7 rifles- Converted from M1933 short rifles/carbines and M1916 short rifles in the 1950s.

    FR8 rifles- Converted from M43 short rifles in the 1950s.

    Larry Gibson had a good write up on this for us.


    http://castboolits.gunloads.com/showthread.php?p=428029

    Quote Originally Posted by Larry Gibson View Post
    manleyjt

    NO comment as to how suitable a certain firearm is to a certain chambering but I would like to keep at the fore front of our minds that the three rounds are not one in the same.

    Externally the dimensions are the same. Many think there is a difference between the 7.62 NATO and .308W based on chamber dimensions (headspace varience gets the biggest attention). Actual cartridge exterior dimensions are the same. Ever wonder why there are only .308W loading dies and no 7.62 NATO dies? The answer is because they are the same dimensionally.

    @e also need to keep in mind the different working pressures for the 7.65x51 nato and the 308 win, 50K and 62K respectively. The 50K psi figure is not necessarily correct for the 7.62 NATO. The MAP (Maximum Average Pressure) for M59 and M62 is 50,000 psi. However the MAP for M80 can be from 45,000 to 65,000 psi depending on temperature. (TM 9-1305-200 dtd June 1961, Small Arms Ammuntion). Also the method of measuring 7.62 NATO pressures is with a gas peizo-electric transducer located at the case mouth. This method does not capture the peak preassure as high as other methods do. As I stated previously, my measurements of various types of 7.62 NATO pressures gives figures from 48-58,000 psi. The average for M80 type ball is in the 52-56,000 psi range which is above the 50,000 psi often quoted. I have yet to find any 7.62 NATO or .308W that comes close to the 62,000 MAP of the .308W. My testing has been out of 3 different rifles with 3 different twists. The 10" twist gives consistantly the highest pressure of the 3 rifles. There can be alot of difference in how the metalurgy reacts once you cross into the different regions of the stress/strain diagram or when calculation for thickwalled pressure vessels ( those calculations can be used for barrels of firearms according to my mechanics of materials professor, I am no expert so have to relay that on to someone who is).

    Once again a reminder that 7.62x51, 308 win, and cetme round are not equal. even though they are very close in dimensional aspects.

    I believe the CETME was loaded with lighter bulletts at a lower pressure/velocity to make automatic fire controllable in the model 58 CETME automatic rifle? Is that correct in the historical context? No it isn't. The CETME rifles were a redesign of the Stg44 rifle of German use in WWII. It had a delayed roller lock up and functioned fine with the intermediate 8.9 Kurz cartridge. When redesigned for use with the higher pressured and less tapered 7.62 NATO case the CETME rifle was quickly found, after fielding to their army, that the rifle would not reliably extract the cases during firing. The solution was the lower pressured cartridge with a lighter bullet that gave a lower recoil impulse. Hence the CETME cartridge was a stop gap cartridge simply to make the fielded CETME rifle reliable. The German engineers then discovered that fluting the chambers solved the extraction problem and all CETME rifles were recalled and the chambers fluted. The production of CETME ammuntion ceased at that time as it was no longer needed. That's why it's very hard to find actual CETME cartridges (anyone seen one?). The 7.62 NATO cartridge then once again became the standard cartridge for use in CETME rifles. CETME bullet was speced at 7.25 gram (approx 112 grain) at 760 m/s (approx 2493 fps) versus 7.62 nato at 9.5gram (approx 147 grain) at 840 m/s (approx 2756fps). The 7.62 nato has so many variants for bullet weight that it is mind boggling I chose to referenc ethe M80 service cartridge in my estimations above, but the range rather amazing. NATO requirements for 7.62 ball ammuntion are a bullet of 145-155 gr at nominal 2700-2750 fps from a 22" service rifle. That does give leeway to a lot of variations.

    I hope that some of the above is correct as I had to dig into some of my reference books for it and as previously said there is some variation in the written specs.

    Any corrections you have would be appreciated, I will try to make sure the above texts reflect what was the actual specs.

    Larry Gibson
    Your FR-7 was converted small ring 93/95's mausers for 7.62 Cetme cartridge a lower pressure version of 7.62x51 NATO but NOT the same spec's.

    If you look on the rifle the caliber does say 7.62. It does NOT say 7.62 NATO. These rifle were made to shoot the 7.62 CETME round which was a slightly downloaded 7.62 Nato round. It was downloaded for two reasons. Firstly to make it safe to shoot in the small ring Mauser & CETME. The second reason was to make controllable full auto fire possible in the CETME. The CETME had real control problems with the NATO round on full auto during testing. Our own US ARMY also fielded ammo to try and make M14 on full auto more controlable in the end we just took out the selector switch.

    Can you shoot 7.62 NATO and commercial 308 Win in this rifle, yes and no. You can't do it 100% safely and it is going to be hard on the rifle, very hard.

    I know of stories of people that have run hundreds if not thousands of 308 win through their Spanish Mausers without a problem,
    SAMCO the importer had HP White labs test to destruction


    Keep in mind that Garry James was paid to write that infomercial and he was paid by the importer. People with a financial incentive are not going to be objective. Or have you never had a bad experience after bought something you saw in an advert?

    Why would SAMCO spend so much time “proving” that these rifles are safe? Maybe it is because they have a deserved reputation for being defective.

    SAMCO sent a number of M1916's to HP White. We don't know if the receivers tested were late model or early model. We don't know if the rifles were rebuilt from 1893's or were new M1916's.

    but I also know of some that have had very bad experiences with escaping gasses when a case let go.

    This Swedish Mauser is the exact same action as a Spanish Mauser. Don’t know what happened here but there is a cracked receiver ring and blood on the ground. Obviously an over pressure event of some sort, and the shooter was not protected by this old action.



    Wear your shooting glasses for sure. Here's another take on it.

    http://www.falfiles.com/forums/print...hreadid=317683
    Posted by Kenshi on September 26, 2011 15:15:

    quote:Kenshi I'm not doubting you word and I appreciate the info, but can you show me any data where it states a Spanish mauser or FR7 can't handle the pressure of a 762X51 or a 308W? If it was designed to handle 45k psi, it shouldn't go kaboom at 50k psi. That would be a mighty small window of safety. If I shoot mine it will be with 762X51 so I don't really see a problem.



    First let me say that in my past life I was an Aerospace Structural and Weapons design engineer, and a Reliability and Maintainability engineer for the Lockheed Skunk Works in Palmdale Ca. Additionally I am an A&P Mechanic, a Master Machinist, a Certified Welder, and a Gunsmith with over 30 years of experience. I designed and tested "things", including weapons, for the F117, F22, F35, and "others". I am a Bladesmith and a Blacksmith.

    In my job as a Reliability and Maintainability engineer I was tasked to test many items under increasing stress and pressure until they failed. I learned to recognize the failure modes, point of failure, and what the failure trends would be, at times by just examining something. Examining a somethings design criteria, material selection, the design itself, and the metallurgy to decide what the point of failure and point of catastrophic failure would be is what l did for a living, and I did that very well and it made me a better design engineer because of it.

    When speaking or writing of failures, material failure and catastrophic material failure are two distinct and separate failure categories and modes.

    I agree that something with a designed operating pressure of 45kpsi should safely handle a 50kpsi operating pressure and this was no doubt a factor in the re-barrel and chambering of the M93/FR7 to 7.62 NATO by the Spanish Military Engineers as that is within the common minimum IRL designed engineering safety factor of a 20% over build.

    Without access to the Mauser design notes I would have to err on the side of caution and "assume" a 20% engineering design tolerance is what was actually used. I do not think that one would see a "Kaboom" (catastrophic) failure with a 5kpsi over pressure as that is approximately 11% of the design pressure. There would be an increase in overall stress however and recognizing the simple fact that all stress in accumulative, it would definitely increase to some degree the failures seen. Whether or not that is acceptable depends on the criteria they used to evaluate the design and design changes and I (without the design notes they used in the modification) can not obviously "speak" to that.

    The issue of soft receiver locking lugs and the bolt to receiver issue is a different one and is dependent of the metallurgy and elasticity and recovery limits of the metal and the forces (bolt thrust) being applied.

    Bolt thrust is dependent on a number of variables which include; cartridge taper, surface area of the cartridge base, case lubrication, case adherence, and instantaneous chamber pressures. Between two cartridges of equal taper, no lubrication or adherence changes, and equal case base area it is a simple mater of multiplying cartridge base surface area by chamber pressure to get a bolt thrust value between the two.

    SOOOO based totally on the foregoing is it OK to re barrel, chamber and shoot 7.62 NATO Spec (7.62x51mm Mil Spec) in a M93 Mauser action in good material shape? I would say yes it is OK based on the foregoing discussion.

    Any and all .308 Winchester loadings? HELL NO!! What is the pressure of the specific .308 Win loading one wants to use? In absence of data one MUST assume a 62kpsi value. To do otherwise is moronic and begs the answer of just what Darwin award is one trying to win for their family to display?

    Because 7.62 NATO "looks" like .308 Winchester they ARE the same and are interchangeable? If anyone want to talk specific MIL SPEC vs SAAMI spec we can do that, there is A LOT more here than just a pressure difference.

    It should be very easy to see why there is a bolt set back issue with the M93 Mauser action and the .308 Winchester cartridge.

    An action designed for 45kpsi handling 50kpsi and the relatively minor increases in bolt thrust is one thing. Being designed for 45kpsi and handling 62kpsi and a major tonnage increase in bolt thrust is entirely something else. Is a catastrophic failure of the action also possible under these conditions? Depending on the health of the action YES. Maybe not today, maybe not tomorrow, but next week? Being a firm believer in Murphys Laws of engineering, it is just a roll of the dice away at these levels of stress.
    So you see the FR-7 is not a "safe" conversion, reason being, it's built on a small-ring mauser action not originally designed for the maximum pressures invloved, these actions can be identified in that they are typically "cock on closing" type, that is, the bolt fully cocks on the return stroke, you can feel the spring tension when it's doing this.

    These actions also are not rated for that kind of pressure, and can develop what's known as "receiver lug setback" where the lugs on the bolt are literally slammed into the receiver with such force that they'll indent the receiver due to softer steels and increase the head space and you chance of brass failure and release of Very High Pressure gases aimed at the shooter!.

    You want a .308 Mauser? Start with a m98 action (large ring action) these actions are much stronger, bolt is fully cocked upon lifting, bolt has 3 lugs on it(2 in front 1 in the rear, (a "saftey lug") not just 2, the receiver ring is a 1/8 larger than a small-ring action, pg 85 in Jerry Kuhnhausen's Book "The Mauser Bolt Actions, A shop manual Says this,


    "MauserM91-M96 actions,even in fully serviceable or in as-new condition must not be rebarreled and chambered for,or fired with, higher pressure cartridges than the action was orginally made for. An example of stretching this rule is found in the arsenal rebarreling and chambering of M93/M95 small-ring Spanish Mauser actions to fire 7.62 CETME cartridge The M93/M95 actions used were orginally made for lower pressure 7x57 Mauser cartridges, After Conversion these rifles and carbines were redesignated as 1916 Models, at normal temperatures the 7.62mm CETME cartridge generates pressures in roughly the 41,500 -42,000 CUP range, in a correctly dimensioned chamber and bore,
    To compound the problem above,a 7.62x51mmNATO (or .308 winchester) cartridge will chamber in a 1916 Model 7.62 CETME chamber However, a 7.62 NATO or a .308 Winchester cartridge can generate pressures of, or about 55.200 CUP. THIS PRESSURE RANGE IS DANGEROUS EVEN IN A WELL HEAT-TREATED GERMAN OR SWEDISH MADE SMALL RING M91-M96 MAUSER ACTION BUT, IN MY OPINION, CAN BE PARTICULARY DANGEROUS IN THE MUCH SOFTER SPANISH MADE ACTIONS, A lot of Spanish made M93-M95 Mausers are still around that are chambered for the 7x57 cartridge. Due to the known softness of the Spanish made Mauser actions and limited receiver/barrel thread bering area etc, most mfg's of 7x57 Mauser ammunition restrict operating pressure to as close to 37,000CUP as possible as a saftey factor...
    So, there you have it, from the man himself...

    And sorry if I got off track a little but I don't want any one hurt by unsafe conversions, weapons are best if used in their original caliber.
    Last edited by Artful; 10-17-2011 at 07:43 AM.

  18. #78
    Boolit Bub
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    Yugo Mauser m-48, short, hefty enough to know your carrying something solid, Sub MOA @ 100 yards with Prvi 196, Lee 175 RN or Hornady 195 grainers, it will shoot anything...top it off with a set of mojo sights and you have a real nice rifle for short money - IMO...
    Let Your mercy, O LORD, be upon us, Just as we hope in You.
    (Psa 33:22)
    “Our Constitution was made only for a moral and religious people. It is wholly inadequate to the government of any other.” -John Adams

  19. #79
    Boolit Grand Master Artful's Avatar
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    Quote Originally Posted by vintagesportsman View Post
    Yugo Mauser m-48, short, hefty enough to know your carrying something solid, Sub MOA @ 100 yards with Prvi 196, Lee 175 RN or Hornady 195 grainers, it will shoot anything...top it off with a set of mojo sights and you have a real nice rifle for short money - IMO...
    And they are importing them again - J & G Sales has them for like 200.00

  20. #80
    Boolit Master
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    I vote 03A3 0r M1917. Have two A3s, one from CMP and one built from a drill receiver, both are accurate, good sights, and the two groove barrels can't be beat for CBs. Other possible candidate is the Swiss K31, usually are in excellent condition, sights are better than the Mausers, and they are still not too pricey, although ammo is an issue (if you are alreay into reloading not a big deal). K31s have a rep for accuracy both with J and CB.

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Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check