Working on a HP load...'Barrel Lengths Matter'

[35remington]

Virtually all the powders you list peak and fall off in pressure before the bullet base clears the cylinder. Most of the Alliant powders are similar in base formulation.

The limitation therefore is mostly due to pressure.

When you draw that snubby from concealment, the powder will be crowded up near the bullet. And then the velocity you thought you were getting will be in actuality around 100 fps slower.

With standard pressure loads Unique will top out at about 800-810 fps with a 158 in a snubby. Permissible loads of power pistol will beat that by about 40 fps but that's most due to loading it closer to the top end of standard pressures rather than due to any burn rate differance. Both powders are noticeably position sensitive.

Test for velocity and expansion powder forward or you will be missing out on real life modeling.

[OS OK]

Virtually all the powders you list peak and fall off in pressure before the bullet base clears the cylinder. Most of the Alliant powders are similar in base formulation.

The limitation therefore is mostly due to pressure.

When you draw that snubby from concealment, the powder will be crowded up near the bullet. And then the velocity you thought you were getting will be in actuality around 100 fps slower.

With standard pressure loads Unique will top out at about 800-810 fps with a 158 in a snubby. Permissible loads of power pistol will beat that by about 40 fps but that's most due to loading it closer to the top end of standard pressures rather than due to any burn rate differance. Both powders are noticeably position sensitive.

Test for velocity and expansion powder forward or you will be missing out on real life modeling.

That's just the information I'd like to read...where did you get this?

charlie

[35remington]

Ballistic modeling programs and long held knowledge I guess. One of the most commonly held but mostly false beliefs is that "fast"powders and "medium" powders (e.g. Bullseye and Unique) have vastly different performance potential in short barrels.

In actual fact, if you're getting considerably more velocity with one than the other you're running at considerably higher pressure. The powder is almost fully consumed before the bullet gets near the snubby muzzle.....and pressure best consumes powder, not barrel length. A longer barrel just gives low pressure loads more area to deposit powder upon.

Very few appropriate 38 Special powders throw any appreciable quantity of unburnt powder out the muzzle. Powders appropriate for the 38 are all fast. Unique Herco and Power Pistol are of the same ilk, and really are not all that much slower than Bullseye.

[Rattlesnake Charlie]

You might want to consider a full wadcutter. Can't count on expansion at what a .38 snubbie does. Go with full bore diameter and some penetration. The .38 snubbie doesn't penetrate much.

[35remington]

Not with many expanding bullets is penetration much over the FBI.minimum. Full charge wadcutters go about 23-24 inches in gelatin, and the SWC's about close to fifty percent further than that.

12 inches is considered minimally acceptable and as long as they don't expand too much your loads will do that. The challenging part is expansion and velocity performance with the powder forward in the case. And you thought you were having a tough time already!

[OS OK]

Not with many expanding bullets is penetration much over the FBI.minimum. Full charge wadcutters go about 23-24 inches in gelatin, and the SWC's about close to fifty percent further than that.

12 inches is considered minimally acceptable and as long as they don't expand too much your loads will do that. The challenging part is expansion and velocity performance with the powder forward in the case. And you thought you were having a tough time already!

This last test went like this...(as all the others did also)
1'st shot...cocked pointing at the ground then raised chest high and pointed at the end of the pipe then fired...(powder should have been in the front of the case...right?)
#'s 2-3-4&5 were cocked at chest level while the snubbie was pointing at the target pipe...wouldn't you think these rounds had the small load of Bullseye scattered from one end of the case to the other after recoil of no. 1 shot?

In your explanation, how did this affect my test?

charlie

[35remington]

Test multiple rounds with powder definitively forward to get a good representative average.....then figure when the SHTF the lowest possible velocities will likely occur. The first shot has most of the money riding on it. If the bullets work at the lowest possible speeds you will encounter, you are unarguably golden if you somehow get lucky enough to have the powder to the rear for a change.

Powder can be anywhere after the shot. It is not inconceivable that shooting may position powder to the front as the gun recoils rearward while the powder may try to stay in place.....but it can bounce around, too. Positioning beforehand then comparing results to "raise and shoot repeatedly" will tell you where the powder is in the case.

Despite claims you may hear elsewhere, most powders are position sensitive in the 38. I repeatedly and extensively test for it. I hate guessing.

[Blackwater]

I think .35 gives you good advice, OS OK. .38 snubby loads are one of the most problematic in realoading, I think. It's been a long time now, but I once carried a M-60 S&W on my ankle when visiting some parolees that liked to keep volatile lackeys around rather than Dobermans, etc. I was fine with my .357 loads, but what to carry in the M-60? I tried WC's with full powder load for 158's, 158 SWC's and the 168 gr. Keith bullets. Wasn't satisfied with any, but tended to like the Keith bullet a little better than the others.

Then I read a load in one of the glossy mags about a snubby load that seemed kind'a hot, but I tried it. Can't remember who printed it, but still remember the load. It was 7.6 gr. Blue Dot with a 158 gr. SWC, and it was what the writer had chosen to carry in his snubby. I tried it, and it seemed definitely the most potent load I tried. I'm sure it's +P (article didn't mention pressure levels) and suspect it's +P+, but I never shot many, other than to verify POI. The bullets I used were some very soft 158 gr. Taurus SWCHPs, with the deepest HP I've ever seen. I think it went 2/3 the length of the bullet towards the base.

Judging by recoil, I wouldn't fire many of them and practiced with std. or some +P .38's. My gun never loosened up materially, but remember, I didn't shoot many of these at all other than for testing and establishing POI in the fixed sight M-60. I do NOT recommend this load, and can only relay my experience with it. It'd expand those soft SWCHP Taurus bullets to near quarter size at close range in wet newsprint, and that was definitely the best load I ever got with it.

To tell the truth, I never really saw any major advantage in any of the other loads, one over the other, and mainly preferred the Keith bullet, until I found that load with the Taurus bullets, because I figured it'd be most reliable in penetration. Also tried the Lee 150 SWCHP, which came out lubed and ready to load at 142 gr. Cast soft with some tin to help hold it together for better penetration, I got some expansion from it, but wasn't that confident it was enough to make much of a real difference, and mainly just relegated myself to having to place those anemic loads just right instead of trying to soup them up enough to get the kind of power I wanted.

Don't know if any of this helps, but I offer it FWIW, if anything. For my little DS, I plan on loading hard cast FWC's or the Keith bullets loaded to std. pressure, and just doing what I did before, and just planning on placing the bullets well. A well placed .22 beats a fringed .50 any day. Just my experience.

[fredj338]

I've had that concept for several decades now, I get that part.

I believe that fast pistol powders need at least two inches of barrel to make full pressure.
I believe that slow pistol powders need around six inches of barrel to make full pressure.

Rifle powders need +/- nine inches of barrel to make full pressure.

'The Wizardry of Propulsion'

All of the above, I believe is...give or take a fraction of an inch. I have the technical write up on rifle powder and pressure/temp./speed/% of powder used at a given length down barrel...I've just never found a comparable write up (white paper) done on specifically pistol powders.

I believe that a snubby is marginal at best for working up pressure/speed...these faster loads you fellas have prolly put a flame out the front end and some large percentage of powder is consumed out there in front of the muzzle. That means that you had a faster, higher pressure load than you actually clocked in the snubby and if it wasn't worked up in a six inch or better barrel, it possibly could be over the top if you go by speed alone and don't limit yourselves to book values regarding maximum pressure.

All the above and the barrel and cylinder gap, fitment of cast, ignition and how you hold your mouth at any given time...all have determination in this mix...it ain't as simple as the dang speed of the powder.

charlie

I still don't think you are understanding the slow vs fast powder issue. A longer bbl will get better vel with slower powders because there is more time for the powder to burn completely. Peak pressure are achieved within the chamber, so a bbl being short or long has nothing to do with peak pressures.
Generally, you get highest vel with slower powders, just fact, regardless of bbl length. Without a chrono, you have no idea what vel you are getting. The fact the LHP expands with one powder & not the other is vel related, not burn rate related. You may just need more slower powder. If you are loading say 4gr of BE vs 4gr of W231, well yes, vel will be lower, but that is to be expected. Load 5gr of W231, you will get higher vel with sim pressures.

[fredj338]

Virtually all the powders you list peak and fall off in pressure before the bullet base clears the cylinder. Most of the Alliant powders are similar in base formulation.

The limitation therefore is mostly due to pressure.

When you draw that snubby from concealment, the powder will be crowded up near the bullet. And then the velocity you thought you were getting will be in actuality around 100 fps slower.

With standard pressure loads Unique will top out at about 800-810 fps with a 158 in a snubby. Permissible loads of power pistol will beat that by about 40 fps but that's most due to loading it closer to the top end of standard pressures rather than due to any burn rate differance. Both powders are noticeably position sensitive.

Test for velocity and expansion powder forward or you will be missing out on real life modeling.

In all my chrono testing with various calibers, NEVER seen a 100fps spread by tipping the bbl up, never.

[35remington]

BW's comments are pertinent.

Speaking for myself, and considering controllability and ballistic consistency along with lesser penetration and greater "per inch" energy transfer than SWC's, the ammo I carry in the gun is wadcutters if loaded to standard pressure. Reloads are more speedloader friendly bullets.

Frankly, from what I know and have tried, getting standard pressure SWCHP's to expand from a snubby is probably not gonna happen with most powder position forward orientation. The upper end of Plus P handloaded pressures are necessary before it reliably occurs with powder forward.

For illuminating results try factory Plus P SWCHP's powder forward to compare. The bullets are quite soft and possibly partly due to variable powder position issues these have a spotty record for "mushroom" expansion as well.

Do not get fixated on the classic mushroom shape. If it bumps up to a cylindrical shape it will go about 18-19 inches in gelatin and this is probably ideal from a snubby. This is pretty much what the FBI load does out of snubby barrels and it is highly thought of. If you accomplish the same you may be in a better position than you realize in terms of being well armed.

[35remington]

Fred, I have extensively documented tests here where I see that all the time. Be very happy to point you to it regarding the 38.

With rifles and loads like a partial case full of 4895, it may be 200 fps or more. Testing for it has nothing in common with unicorns.

[yondering]

I've had that concept for several decades now, I get that part.

I believe that fast pistol powders need at least two inches of barrel to make full pressure.
I believe that slow pistol powders need around six inches of barrel to make full pressure.

Rifle powders need +/- nine inches of barrel to make full pressure.

Respectfully, your beliefs are off by a long ways in this matter, and it's preventing you from fully understanding your load. Peak pressure in most handgun rounds is reached very quickly, with the bullets very close to the chamber. In rifle rounds peak pressure is generally achieved within the first few inches of barrel.

Ignoring velocity is a very "unique" approach to making hollow points work, since velocity is one of the primary factors in how well and if they work.

[OS OK]

You are absolutely right, I beg your pardon and everyone else's...peak pressure is at the 'about 1 inch' mark with rifles.

I had to go back and re-read an article..an article titled 'The Wizardry of Propulsion' published in "SPEER, Manual #7 for Reloading Ammunition", pub. 1966-7. author; DR. Edgar L. Eichhorn.

I had my facts 'bass ackward' and was wrong. Thank you for persisting and getting me to back up and re-group!

I had it in my mind that pressure was at max. at 9 inches when it is actually 100% of the powder is consumed by that point. It's not safe for me to assume that I remember something correctly anymore.

Now I can clear that garbage from what little grey matter I have left and re-think this post from the start.

charlie

[Blackwater]

Well, OS OK, that's a big boat yer travellin' in when it comes to th' memory thing. My forgetter is the only thing I've got that's gettin' stronger!

[OS OK]

Thanks for the kind words Dennis...I hate eating 'crow...munch-munch'...somebody pass me a beer to wash it down!

[runfiverun]

think about it as time under peak pressure.
the other advantage to the slower powders is they fill the case.

[yondering]

I hate eating 'crow...munch-munch'...somebody pass me a beer to wash it down!

No worries man, we all get mixed up sometimes; good for you to realize it and move forward. I figure if we're all here to learn something (or re-learn it) and leave the egos at the door, we can get a lot farther than we would if we don't eat crow when it's appropriate.

[Forrest r]

Usually older outdated powder like unique will show extreme signs of position sensitivity. Hence the huge sd's/100fps+. Any reloader should take a hard look at their powder choice when it comes to heavy loads in a snub nosed revolver.

Titegroup:
While not my 1st choice of powders it will outperform bullseye in 38spl p+ loads. It is also an extremely high energy powder hot burning powder that takes position sensitivity out of play.
Power pistol:
Another high energy powder that has a hot consistent burn. You can look at unique and pp and say their next to each other on the burn rate charts. But that isn't telling the whole story. It's the temp at which it burns that makes it be extremely consistent shot to shot and not be anywhere near as position sensitive as powders like unique.

That's what makes pp such a high performing powder in 38spl p+ loads. You'll find that you can load max loads of power pistol with 135gr to 160gr bullets and you will not see any huge jumps in velocities from the lighter bullets. Don't know if anyone ever paid attention but alliant doesn't list any pp/lead bullet loads in the 357. But they do in the 38spl. If you want a real eye opener you should contact allaint and ask them why!!!!

When I tested pp vs 2400, the 2400 had similar performance for the @ velocity for the 10-shot/10 bullet strings (100 total shots). But the es's were different.
The 2400 had a es around 70fps with every different 10 bullets/10-shot strings.
The pp had a es around 35fps with every different 10 bullets/10-shot strings.

Actually I think the OP is doing pretty good with his testing. He's using nothing more than a "target" powder and isn't even using full house 38spl standard pressure loads with it in a snub nosed revolver.

Nice job opening up those hp's.

[OS OK]

Mr. yondering, now that I've had time to pick the feathers out of my teeth I want to re-ask this question...

1'st shot...cocked pointing at the ground then raised chest high and pointed at the end of the pipe then fired...(powder should have been in the front of the case...right?) <Could this shot be the low velocity shot that caused the only one of five not to open up...you can see it was considerably slower?
#'s 2-3-4&5 were cocked at chest level while the snubbie was pointing at the target pipe...wouldn't you think these rounds had the small load of Bullseye scattered from one end of the case to the other after recoil of no. 1 shot? <If indeed the powder charge did spread out in the voluminous case, in your opinion, did these shots do the work to mushroom those remaining four casts?

*If that minuscule amount of Bullseye is going to be so problematic...am I behoved to use the bulkiest powder possible to help eradicate this problem, something akin to the good old standby...Unique?

Should I set the chrony up and fire shots purposefully 'powder positioned' to compare FPS? How did you compare?

*The only reason I said earlier that I wasn't going to worry about FPS is that it takes 5 more rounds, 10 total in each test looking for the perfect mushroom. I thought I'd just keep working at the increased speed and just find out later what it was only after I had 100% results...it is what it is and I knew I had to get into the 800 FPS range. I just got tired of carefully weighing those charges only to find myself in the mid 700's, get my drift?

Thanks for your considerations...charlie

*Another consideration I had in mind was to develop a load that was at least .2'ths under maximum...I had hoped to make these rounds using a powder throw and I just don't like to throw up next to the outer limits, otherwise I have to use the auto-throw and trickle up to what I want. That works fine but I would have liked to save the time.