Alloy weight question

[jsizemore]

Ya'll figure these folks just stuffed anything in their rifle and let fly?

https://en.wikipedia.org/wiki/Creedmoor_Rifle_Range

They exploited the benefits of cast bullets more than we do cuz that's all they had. WE learned from their thoughts and work. I use 70+ year old molds that are as good or better than made today. Of course they were the custom molds of their time. Most of the so-so stuff didn't survive the trip to today.There were hacks then just like there are now.

[fredj338]

Like others have said.....it doesn't matter. And when loading use loads for the published weight the bullet is supposed to cast and don't try and find data for for 232 or 248 grain bullets.

Or use heavier bullet data & work up. We should always work up loads, but data for 240gr lswc wont work well for a 265gr WNFP.

[kevin c]

Oh, I freely admit to indulging my OC side when it comes to alloy. From a practical standpoint, though, what I really want is consistency for the tens of thousands of boolits I cast each year for competition, where, per the rules of the game, I have to meet a minimum threshold of bullet weight times velocity. Using the same alloy composition, whether or not it really is the 95-3-2 I aimed for, gets me the same weight bullet from the same molds so I know using the same powder charge will get me a predictable range of velocities.

That’s what works for my particular application. YMMV.

[Cast10]

I just had Tom make me a mold. It was published to drop at 117gr using COWW. My mix is SOWW + some Hardball to add in SN. I end up around 1% SN 2.57% SB and 96.4% PB. In the ordering process, you must enter the alloy you will be using to give Tom and idea of what you want. In actuality, my new mold dropped at 119gr. Perfectly fine with me. I don’t think you’ll find a large discrepancy. Also, if you do find a difference, you can drop back on how much SN/SB you are using. I get great fillout with 1% SN. By adding some SOWWs/Pure Lead you can water it down a bit and this will also add some expansion you won’t see with straight Hardball or Lyman 2. All good info above. These are definitely the folks to ask!

[white eagle]

I always in addition to weight get the boolit mold oversized so I can size them to the diameter I want and need for a particular firearm

[fredj338]

Oh, I freely admit to indulging my OC side when it comes to alloy. From a practical standpoint, though, what I really want is consistency for the tens of thousands of boolits I cast each year for competition, where, per the rules of the game, I have to meet a minimum threshold of bullet weight times velocity. Using the same alloy composition, whether or not it really is the 95-3-2 I aimed for, gets me the same weight bullet from the same molds so I know using the same powder charge will get me a predictable range of velocities.

That’s what works for my particular application. YMMV.

I cast for PF competition too, but unless you are riding the ragged edge of minimum, variation in bullet weight of +/- 5gr isnt an issue.

[BJung]

From my experience, when I cast bullets using range lead and did not separate the lead from FMJ, large chunks (usually from JHP bullets), and small pieces of lead sifted out, I had varying but high bhn measurements. The weight of the bullets I cast were heavier than the mold maker. Then I separated my recovered lead into groups from FMJ/JHP, large chunks, pellets, and .22lr. FMJ/JHP and pellets were measuring at 9 BHN, Pellets around 7-8, and .22lr around 11. I cast bullets with these alloys and each at a 40:1, 30:1, and 20:1 ratios. As I increased the tin, the weight dropped slightly. The pressure needed to size all bullets were slight compared to casts from all my lead melted together. Alloys for .45-200 mold bullets cast at 200-203gr for alloys 40:1,30:1, 20:1 throughout. My bullets cast from a 40-160 mold cast 160gr bullets in its original alloy without extra tin. This tells me that alloys effect weight. And, if your bullet is casting light, try adding pure lead to your mix. I don't know what you are casting but If there is tin and antinomy in your alloy, you can water drop. And if you can PC and add a GC, the better. I hope this helps.

[kevin c]

I cast for PF competition too, but unless you are riding the ragged edge of minimum, variation in bullet weight of +/- 5gr isnt an issue.

I do know folks who think 128-129 PF is fine. If they had a 10 grain swing in a 124 grain bullet, based their load on a high weight bullet but were unlucky enough to have a couple light bullets pulled for weight at Chrono, that ~8% drop in PF would mean shooting for no score at a major.

My Production and Carry Optics Glocks like ~135 PF, and I use a 148 grain bullet, so I personally don’t worry about it, especially since my alloy and molds give me very consistent weight bullets. A ten grain range in weights would get me close to trouble, and, with the typical chrono voodoo encountered at different matches, maybe into it. I like having a cushion, and for me bullet consistency is part of that.

[Rickf1985]

What is PF competition?

[JonB_in_Glencoe]

What is PF competition?

PF is power factor.
in IPSC (USPSA) competitions (and probably other competitions) ammunition is rated on a scale of power factor. for IPSC it's "Major" and "Minor" and they are scored differently.

[kevin c]

Power factor minimums in action pistol sports insure competitors’ hand loaded ammo aren’t all mouse flatus cheater loads. In certain divisions you actually score more points for the same hit if your PF meets a certain (“major”) threshold. You shoot for no score if you fall below the minimum (“minor”) threshold.

Ammo is tested through the competitors’ guns during major matches at the Chronograph station by taking a sample of ammo from the shooter, pulling one or more bullets for weight, and shooting a few for velocity measurement. Bullet weight in grains times velocity in fps divided by 1000 equals power factor.

[Rickf1985]

Glad they did not have all those rules in 1968!!! Sounds like race car rules, those I did deal with back then.