[JB70]

Recently I purchased both an ACR and a SCAR.

I made it the range today and had some time before the rain set in. My test today was sight both in and run various factory ammo and gather results. ACR - optics Eotech XPS 3 with 3x Gen II Magnifier SCAR - optics Trijicon 4x32 TA31F After sighting in I wanted to see how picky each rifle would be with ammo. My test is a five round group using a 4inch by 4inch box at 100yds. I am not measuring shot groups at this point. What I am looking is the rifles ability to shoot various ammo and preform consistently. If the SHTF fan I wouldn't have time to hand load nor would I be shooting from the bench. I did use my range bag as support for this test. ACR - 55g (2 in the box 3 scattered) 69 SMK (all left scattred) 75g (all high scattered) I was very disappointed and still think BM made a serious error in choosing a 1:9 twist. SCAR - 55g (3 in box 2 on the line very tight) 69 SMK (all5 in box very tight group) 75 (all 5 in group not as tight as the 69SMK). Result ACR - Fail SCAR Pass The recoil of the ACR is NOTICEABLY more than the SCAR, return to target SCAR pass, ACR (no better than my AR so for this test fail) Te next test will be form the bench with various loads until I find the sweet spot and will measure the groups. I do NOT have any faith in BM 1:9 barrels and expect the SCAR will out preform the ACR. I was so disappointed with the 1:9 twist on my AR I put a Green Mountain 1:8 twist and for a cost way less than the DD and other barrels it is a tack driver. More to come.

 

[amstel78]

How heavy is your ACR's trigger versus the SCAR?

My ACRs accuracy is pretty crappy at 100 yards due to the 9 lb pull plus creep. It's still minute of man though, and I'm sure I could hit my target with the ACR if the SHTF. On the other hand, I get 1 to 1.5" MOA groups out of my AR with a 5.5lb trigger and no creep; same ammo, same distance.

 

[BoovarBjarki]

Was your barrel tight on the ACR? Also, the ACR and SCAR have different muzzle devices, so your comparison would have been obvious before shooting about recoil and muzzle rise as they both shoot the 5.56.

ETA: you are also running very different optics.

 

[JB70]

The trigger on the ACR may be contributing. As far as the optic but are top notch, but to be fair I would swap and just to see the results. I don't think they would be any different. Muzzle devices play a part in the recoil yes that is true, but not to the point I am speaking of. My AR with a A2 birdcage seems to have less. Do misread my results. I am not against the ACR or I wouldn't have spent close to 3k on rifle and optics, I would like a 1:8 or 1:7 barrel option. My guess is that with some changes my result might change, but why should I have to at that price point right out of the box? The ACR charing handle is is better design...

 

[Tackleberry23]

The trigger on the ACR may be contributing. As far as the optic but are top notch, but to be fair I would swap and just to see the results. I don't think they would be any different. Muzzle devices play a part in the recoil yes that is true, but not to the point I am speaking of. My AR with a A2 birdcage seems to have less. Do misread my results. I am not against the ACR or I wouldn't have spent close to 3k on rifle and optics, I would like a 1:8 or 1:7 barrel option. My guess is that with some changes my result might change, but why should I have to at that price point right out of the box? The ACR charing handle is is better design...

I'm glad you're not closed minded to this (ie-willing to switch optics, etc.) the muzzle device can play a role, but not with first shot accuracy. The only disparity would be with follow-ups or an evaluation of the recoil. I had the same brake as the SCAR on my ACR and it had much less recoil and muzzle rise. That's the point of having a muzzle brake. SCAR, frankly has more need of a muzzle brake because it's lighter (accentuate the positive).

Changing optics would be a good idea for a fair comparison.

Frankly, I'm surprised to see that your results with heavier loads was so poor with the ACR. One user here tested the ACR barrel and found it to be a 1:8 twist. In fact many variable load tests for the ACR that I've seen online and in magazines puts better groups on the heavier loads. It seems to work best with a 62gr in my experience. If you get closer to 77 or 79gr, you might be stretching a bit, agreed.

Still, a decent function test. Just surprising. That's my .02. Also jealous that you an afford to get all that gun money together. Have fun.

 

[JB70]

I intend on getting another brake and if I can find a 1:7 barrel. Then I will run them again and compare apples to apples. Still disappointed that I have to make the changes, more so becuase it just seems I have crap luck with any 1:9 barrel.

I have searched for ACR barrels but can't find any, does anyone know who is making them?

 

[Sentll]

Its wierd, Military Arms did a comparsin and found the accuracy to favor the ACR slightly. I had an offer to trade my ACR for a SCAR 16s, and I turned it down. My ACR has worked flawlessly and has impressed me in all the fields ive tested. My spikes AR has got alot of dust on it since the ACR. Now if that offer was for a scar 17s thats a whole different story =) Sorry your ACR didnt work out for you.

 

[JB70]

You might want to do a better "test" for groups before dismissing the ACR's barrel. Your "test" and 1:7 statements don't compliment each other.

I think it is a "better" test. As far as my statements I stand firm, I prefer 1:7 or evan 1:8 barrels. The bottom line is what shoots better for me. I am not bashing the ACR...I will make some changes and see if it preforms the way "I" would like.

 

[Tackleberry23]

I think it is a "better" test. As far as my statements I stand firm, I prefer 1:7 or evan 1:8 barrels. The bottom line is what shoots better for me. I am not bashing the ACR...I will make some changes and see if it preforms the way "I" would like.

That seems a fair response, although I think that further testing may be necessary to make it "apples to apples". Many of us have also made our personal modifications to let the platform, which is still in its infancy, fit us. Personally, I have reprofiled and shortened the barrel, bobbed down the ejection side of the safety selector, and changed some hardware to the barrel wrench. Whatever works best for you. Once you've found that "sweet spec" that fits you, you won't be sorry.

 

[JB70]

Just stumbled upon some info on how to modify an M4 barrel to fit the ACR. It may be above my pay grade but I might take it a gunsmith I know and see what he thinks.

 

[Tackleberry23]

You will likely have to take your barrel hardware over to the new barrel. I'm not sure where you're located, but ADCO in northern Ohio has been doing great work for a lot of SBR people here. You just give them the specs, send it in, and turn around is about a week for most work done that I've seen here. They did my barrel work, and I couldn't be happier. Just be sure to research what modifications would be needed first. There have been some good forums on here on the topic.

http://www.adcofirearms.com

 

[amstel78]

The trigger on the ACR may be contributing.

I bet it is. Swap the trigger and hammer springs out for something lighter; put the ACR on a shooting vise; use a scope; report back.

The only reason I say the above is that I know my technique doesn't suck, but the ACR's stock trigger is absolutely terrible for MOA shooting. It's a combat weapon with a combat spring system designed to strike hard military primers - not a tack driver.