Significant difference in performance, precision ARs vs bolt guns

[Nephrology]

Gas guns are harder to shoot precisely, and have different ergos than most bolt guns. Lighter rifles are much more difficult to shoot precisely.

Any long gun requires a repeatable and stable natural point of aim (NPA), or "index", and I don't take it for granted that I can just pick up any rifle and shoot a perfect group with it. I have to get comfortable with it, and practice with dry and live fire. A lot of the dry practice doesn't involve pulling the trigger--just exploring my NPA and how my body interfaces with the rifle (cheekweld, eyebox, butt position, rear bag, LOP, balance, how the bipod feels when it's loaded, etc). Some rifles just don't fit me, and I'd be hard pressed to shoot the groups you posted.

Also, I suck at benchrest shooting despite having earned a number of precision rifle podium spots. I don't practice shooting from a bench, and my groups show it. If I'm sighting in a rifle, or testing loads, I shoot prone.

So... we can't tell if it's the rifle, the load, or you --unless you can self-diagnose by calling your shots based on feel or how the reticle lifts under recoil. Do you see anything different between your gas and bolt guns? Between the shots that were centered and not?

Thanks, this is helpful. I can't fully rule out that I am contributing - will dry fire a bunch before/during my next range trip out. Will also try a few different positions.
With the gas guns, I don't necessarily see a consistent POI difference so much as just much bigger groups. Given that .223 out of my heavy ARs isn't much more recoil than .22, I also wonder if recoil anticipation/management isn't also a factor, but 6.5 really is pretty pleasant out of these guns, so not convinced that's it either.

Sounds like an issue with your bolt gun or its load. There's a reason why gas guns don't win in PRS.

Ammo was Norma 143gr Golden Match and S&B Precision 142gr HPBT. Have some Federal GMM and Hornady ELD-M on the way as well as single boxes of this and that just to see what the barrel likes.

That said I haven't ruled out that it's an issue with the Bergara either. They seem to have let a lot of lemons out the gate in the last few years with regards to accuracy. I'll give the OEM barrel more time to prove out but eyeing one of the Preferred Barrel Blanks remage style prefits ... Would be nice to get on a barrel nut system anyway for future swaps.

[Nephrology]

It is easier to shoot a bolt gun well than a precision AR so there is something amiss. I could not see your groups, there was an image loading error.

The S&B is not match ammo. I have one gun that shoots it well enough and others that don't. It is fine to break in your barrel for the first hundred plus rounds. You should see better results with the Hornady match 140grain ammo. The Berger 140 match ammo also shoots very well with low SD and ES.

The barrel on the HMR Pro should be good for a 10 round string with that profile. Make sure that the barrel is not touching the stock back to the recoil lug. You can always bed it with Devcon to be sure it isn't the stock.

Make sure the action is not loose in the stock and torqued to the manufacturer's recommendation. Usually 55 in/lbs. You can play with different values here as well.

The suppressor could be the problem as well. Pull that can and shoot it with a brake or with just the thread protector on. Not all cans play well with precision rifles.

After you check everything then dial down the weight on the TriggerTech and dryfire.

Edited to add: I just reread your post and didn't see you had it in the magpul chassis. You can always throw it back in the factory stock torqued to 55 in/lb and see if it tightens up.

Action screws are torqued to 55in-lb in the chassis. Ive shot it in the OEM chassis before and groups weren't significantly different so I am not sure it is that...

1. +1 on trying different ammo. ELD-M always seems to work well for me. My Bergara 6.5 likes Bergers as well as Lapua Scenars.

2. Also +1 on ditching the can for now. Put the rifle in its most basic configuration, then get it working well, then one by one add-on different things and see how the accuracy goes. Last year I bought a rather expensive Fierce rifle and immediately slapped a can on it as well as a fancy scope mount with a fancy scope. Was not getting good groups at all. Pulled the can off, used Plain Jane simple rings and got the rifle shooting awesome. Next step is adding the can back and evaluating the accuracy.

3. Since I brought up scopes. What kind of glass do you have on the gun? And just as importantly, how is it mounted? Scope problems and incorrect mounting are very common causes of accuracy problems. In fact, I sent a Bergara back to the factory one time because I couldn't get it shooting well. I had to take the scope off of it as that's what they requested. They tested it in found it to be perfectly acceptable, 0.5 Moa and sent me the test Target to prove it. I put a different scope on the gun and guess what, it worked perfectly fine for me too now.

Definitely will try w/o can next time. Glass is a Brownells MPO, mounted in Vortex Pro 34mm rings on a Nightforce 20MOA scope base that I installed myself. Torqued and mounted just as I do the scopes on my ARs (though those usually use 1 piece mounts).

The easiest area to start with some pretty consistent match ammo like some Hornady 140 or 147 ELD-M's or Berger 140 or 144 hybrid target ammunition.
See how that works out and post results.

Have some better ammo on order, we'll see how that does