3" group @ 100yrds

BenMara · Nov 21, 2014

So i finally got my good glass on my (only) bolt action. Rifle is a Ruger Gunsite Scout in .308 Win, Barrel 16.5" Twist 1:10, with a PWS Precision Rifle Compensator (PRC). Used Federal XM80C 149gr and PMC Bronze 147gr FMJ-BT to sight in.

I dont know if this is normal, but getting 3" group at 100 yrds. Can move POI, but cant get group and closer.

What do yall think?

rotarymike · Nov 21, 2014

Try without the compensator first. If no change, try different ammo.

A 16" barrel on a .308 is kinda short, but you should still shoot better than 3moa on a new rifle.

mark_b · Nov 21, 2014

I would also check that all of your scope mounts and screws are tight. You might be getting variation because your scope is moving around between shots. I agree with RotatryMike, your setup should be better than 3MOA.

Let us know how it works out for you.

BenMara · Nov 21, 2014

Wish i could take of the Comp, i had D&R put it on. Loosen and retorqued the rings.

BenMara · Nov 27, 2014

Some one mentioned that XM80C isnt an accurate ammo. So what are your thoughts one a Match ammo to purchase with this Barrel 16.5" Twist 1:10?

armaborealis · Nov 27, 2014

A quick search of the interwebs shows the PMC to run about 1.5-2 MOA for most shooters (from a rest with various rifles). M80 ball spec is only 2.4 MOA for the .mil; most of it runs better than that but no guarantees. I have not been impressed with XM193 lately, so maybe XM80 is getting cruddy too.

Chuck Hawks found the Gunsite Scout rifle to run about 2.5-4 MOA. Another reviewer found 1-4 MOA (http://www.guns.com/review/2014/09/10/g ... fle-video/).

So I am not surprised to hear the groups are 3 MOA... You're using 2.4 MOA ammo in a 1-4 MOA rifle. Especially if you are shooting larger groups (5-10 rounds) the groups may be a bit larger than the 3-shot "groups" many advertise on the internet. The scout rifle with ball ammo is intended to get hits on man-size or big-game size targets out to the rifleman's quarter-mile. 4 MOA should be sufficient to get such hits out to 500 yards.

I would run some match ammo through the rifle, off a rest or bipod, and compare the results with the ball ammo. You will probably find that groups tighten up by an MOA or two.

BenMara · Nov 30, 2014

Been doing more asking around, they claim the 1:10 twist is more for heaver/longer projectiles. Some are suggesting anything above the 147gr.

BenMara · Dec 3, 2014

No match ammo @ PSA what gives? Guess ill have to see what ATP has...

armaborealis · Dec 4, 2014

BenMara said:
No match ammo @ PSA what gives? Guess ill have to see what ATP has...

http://www.gunbot.net/ammo/rifle/308/
Plenty of match ammo starting at about $0.80/round. Prvi was the first thing that popped up but there's others. Weidner's has PPU in stock. The PPU match has treated me well in .223.

1:10 is the standard twist of the Springfield '06 and Garand. That twist should be fine with 150ish grain bullets, although it should also stabilize heavier rounds.

Another thought is operator issues. Moving up in caliber often results in a loss in accuracy compared to one's groups with a rimfire. The 308 is reasonable but stouter than, say, an AR or a .22. You might consider some ball and dummy drills with a buddy to rule out human error.

jfeenin · Dec 5, 2014

Some rifles can be finicky about what they do or don't shoot well. Of course higher quality rounds will be more consistent round to round than economy stuff but that still doesn't mean your rifle will like to shoot them. I would play with different brands, weights and bullet types and see what it likes the best.

Ultimately if you want the best accuracy for your rifle it will mean reloading your own and to work up a load that works well you will still need to try different types of loadings and bullets until you find one that shoots as well as you like. Reloading isn't for everyone though and most people find a factory load that works well for them.

Just my 2 cents but only guaranteed for every cent you paid for it. YMMV ;-)