Badly pitted bolt face - poor grouping.

[2cants]

Sorry to hear your frustrated as well Bassaro.

I was pretty happy with the shots - but these were the exceptions. Duplicating them was difficult.

The rifle forend was on a benchrest and butt on bag. Very solid.

Biggest factor affecting them was supporting the rifle. POI seemed to be effected dramatically depending on how firm in the shoulder the rifle was held. FPS Extreme spread showed average of 30fps.

Largest grouping was around 3".

My good load was 40gn AR2208 (varget??) - and this varied mostly on weapon support (degrees of how firm I held it).

Thus I think a free float should eliminate external pressure on the barrel.

Once in stalled I will post results.

 

[Bassaro]

Every time I test loads I do it off my lead sled to remove as many variables as I can. I highly recommend one if you are a reloader for the sole reason of testing groups. I shoot off sand bags when practicing though.

Best powder I found for all things 308 is IMR 4064. I also found some very good loads for 223 with that same powder.

 

[copemech]

2cants, I think yours may do well with the free float so you can negate the pull on the barrel. Looks like you are in the zone at least.

Bassaro, I get the feeling that your is in sommwhat the same condition as mine, yet not as bad. Quit wasting ammo! SEND IT BACK!

Mine threw 6-8" groups, reguardless of ammo at 100 yds. I can half that with my old Colt AR with carry handle open sights.

I got a shipping notice they were returning mine, should be here soon, but no report on what they did as yet. We shall see!

I had one Army marksman and one Marine shooting instructor shoot groups with mine. Both just handed it back and said "it ain't you!" One of them targets went back with the gun as example. This was freefloated, trigger, 3 different scopes, 3 different muzz devices! Splatters like a cow on a flat rock! My SKS is more accurate!

 

[copemech]

Question for 2cants and othere. Are you running cannalures or crimps in your handloads? Is it necessary?

 

[MichiganScott]

Question for 2cants and othere. Are you running cannalures or crimps in your handloads? Is it necessary?

I've never crimped a handload for anything, including .375 H&H bolt guns, M1A's, Garands, and several AR's. If you are concerned about the bullet being pressed back into the case during feeding, you need to find a powder that gives 100% loading density. You can also polish the neck expander ball down a couple of thousands to give the neck better grip on the bullet.

 

[2cants]

Question for 2cants and othere. Are you running cannalures or crimps in your handloads? Is it necessary?

I use a little crimp on them with the...
RCBS AR SERIES DIE SET 308 WIN
used in my Forster Coax press.

I might try without crimp next time at range. Using the Hornady Amax - they don't have a cannelure.

When I sorted brass by weight (which approx. means same internal volume) then my Extreme Spread dropped to between 17fps to 30fps. Still the groups weren't always tight (hence freefloat).

I have read in other forums that there might be some MP10's with incorrectly installed barrels? I will ask my gunsmith to check the clearances when he installs my freefloat (looking at Troy 11" STRX-AL1-11BT-01

Hope it fits...

 

[copemech]

Thanks for that 2cants! Yours is good it seems, mine is not, got it back today, I am opening another thread to discuss my displeasure! Read on!

 

[Shamen]

"6-8 inch groups regardless of ammo" is about what I'm getting. The Sierra GameKing does do better but that isn't much consolation. I've put at least 300 rounds of assorted ammo through mine. No visible damage, the gun is new. Good to hear you're making progress. I'm not consoled at this point. The M&P 10 may not be a keeper for me...