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gutpile
08-05-2014, 02:40 PM
A buddy has a suppresed 308 win wants to try 200-250 grain boolits only thing i can think that would be a problem is baffle strikes with gas checks.
anyone do any loading for a can?

IraqVet1982
08-05-2014, 02:44 PM
Why use gas checks on subsonic? They should be moving around 1100fps or less... shouldn't that abate the need for gas checks?

Lonegun1894
08-05-2014, 03:13 PM
Could you give us more specifics on this, such aswhat the twist is, which bullet, etc? I have a stamp pending and have been doing some load development for mine, and I can tell you that there is quite a difference in what will stabilize in my 1:10" ROT Savage vs what will stabilize in my 1:12" Remington. Then there's the lengths of specific bullets, such as a heavy RN/FN design will stabilize easier than a spritzer of the same weight but longer. Your concern about the GCs is valid, but he may also have issues with the boolit itself striking baffles if he doesn't get his ducks in a row on this. Here is what I am doing and also recommend. Do the load work up in the rifle without the can on it so if there are any issues, you find them and fix them before you take a chance of damaging the suppressor. So far, I have seen things work that I thought wouldn't, and others make me scratch my head cause I can't explain why I can't get them to work. Mainly with some heavier bullets stabilizing in the same rifle when a shorter bullet that should in theory stabilize easier, not wanting to. Now to be fair, I have been pushing the limits a bit on how slow (quiet) I can really go, but you get the idea.

Colohunter
08-05-2014, 05:32 PM
I've been working with the Lee 309-230 in 300 Whisper and subsonic or slightly faster. I have shot it with LLA and powder coat and haven't noticed any leading so far. I think you could load subsonic in the 308 without gas checks. I would consider powder coating to keep the suppressor clean if you can't disassemble it for cleaning.

gutpile
08-06-2014, 03:08 PM
its a 1-in 10 twist i have 160 lee .311 and 185 Lee .312 looking at 200 to 250 grain molds

petroid
08-06-2014, 03:24 PM
Either of those boolits should work fine just work up without the can to prevent baffle strikes as has been said. The lee 185 for me drops at 190. And with PC and gc about 195.

fivel_976
08-08-2014, 01:02 AM
Great info

Shiloh
08-08-2014, 09:20 AM
Plain base soft lead would probably also work well at reduced rifle velocities.

Shiloh

HotGuns
08-09-2014, 12:27 AM
Negative. It will not work.

The maximum bullet weight that will work for a 1 in 10 twist is 180 grains, and if its a long bullet it may not work.
The 1 in 10 twist simply will not stabilize a bullet bigger than that.

Its not the weight that is an issue, its the length of the bullet. In my .308's a 220 grain bullet will hit the paper sideways at 25 yards. It is THAT unstable.

Stick with the 180's or less and you'll be OK.

1johnlb
08-09-2014, 01:39 AM
I shoot the lee 230 bo in my 30 Cal's with 1 in 10 with moa accuracy. In everything from my Schmidt Rubin 1919 to my savage 10fp. It can be done.

303Guy
08-09-2014, 02:55 AM
I've shot 240gr boolits in a 1 in 10 twist. Your 180gr boolits went sideways for a different reason, possibly rifling skid which resulted in lack of spin?

runfiverun
08-09-2014, 11:19 AM
instability is caused by 2 things, not enough speed or not enough grip on the rifling.

Harter66
08-09-2014, 11:41 AM
I have 2 1-12s 30cals that would not stabilize 180s untill the recoil was uncomfortable in both rifles ,1 simply won't,w/ jackets. Now drop down to 175 cast or a 168 jacketed and viola' groups at all velocities tried. The 1-10 does better but a 200 gr spitzer is marginal (1.21 in long) it shoots 1 day but key holes the next. The 30 and 31s at 1-8.5-9 have shot well w/all weights even 200gr spire points in a combo designed around 123-125gr. Cartridge will play a roll in success as well.

303Guy
08-10-2014, 04:08 AM
Boolit shape has a lot to do with stability. Some shapes are stable at subsonic, transonic and supersonic while others are terrible at transonic and others at supersonic and not subsonic and so on. Some shapes become less stable as velocity increases. It's complicated. Put it this way, I managed to get a 55 gr FMJ spitzer boat tail to go nose first in a 1 in 16 twist hornet (it did have some yaw though). Hornady 60 gr spire points shot great in it. I broke all the rules, zero neck tension (actually a clearance fit), rusted bore, oversize neck and throat and so on yet accuracy was superb. So there are rules and there are exceptions to those rules. Same applies to cast. Reading of stability problems makes me want to try out my 265 gr boolit in my Brit on the range (I only fired it into a test tube in which it tracked nose first). I can adjust the mold so I could test different weights. It would be an interesting exercise but it may take a while.

Mike H
08-10-2014, 04:35 AM
Negative. It will not work.

The maximum bullet weight that will work for a 1 in 10 twist is 180 grains, and if its a long bullet it may not work.
The 1 in 10 twist simply will not stabilize a bullet bigger than that.

Its not the weight that is an issue, its the length of the bullet. In my .308's a 220 grain bullet will hit the paper sideways at 25 yards. It is THAT unstable.

Stick with the 180's or less and you'll be OK.

I have a .308 and a 7.62x39,both with 1-10 twists,both shoot a plain base 216 grain cast bullet at subsonic velocities .

Larry Gibson
08-10-2014, 07:02 AM
A .30 caliber cast bullet of 230 gr and not more than 1.48" long will stabilize just fine at 1050 fps from a 10" twist barrel. If jacketed bullets do not hit the baffles the GC on a properly stabilized cast bullet will not either. I have shot lots of subsonic cast bullets through my suppressed .308W with a 10" twist. I don't use the ultra heavy bullets though. The 311299 is the heaviest I have used but mostly use the 311041.

Larry Gibson

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