Suppressors Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

[JSTARSZ]

I have an interesting phenomenon that I have seen occurring on this rifle and was wondering if anyone else has seen it as well with their AAC M4/2000. I am using a Short Action Custom 223 Bolt rifle with a Bartlein 1:8 Twist: The rounds fired are 77 SMK, LC Brass - 24.1 Grains of AA 2460 at 2.75 COA and it crony's at 2750 average.

I normally shoot unsuppressed first and you will see that in the center 1 inch paster with 10 shots. Then I put on the suppressor and shoot the bottom right paster - first shot - the normal 1 MOA left - then the next two shots warm the barrel up and drop it about 2 MOA in total. The next series is on the left lower paster and I correct the elevation up 1 MOA and the windage 1 MOA right. The rifle is still heating up and kind of goes a little erratic. Now the barrel is getting warm so I move up to the upper left paster and shoot a five shot group. As you can see it is getting tighter now. Then I load my last six rounds of the day and move up the elevation one more MOA for a total of two MOA and shoot a six round group - not too bad.

I have had this rifle for about six months and it is a great shooter. I have seen this happen with the suppressor numerous times but I didn't want to come on here until I have seen the data enough to be confident on what I was seeing.

Once the barrel heats up it can shoot well with it but if I let it cool too much between strings I have to go through the whole process again.

I am just wondering if anyone has seen this with their AAC-M4/2000. By the way, shooting a suppressor with a 223 is like shooting a pellet rifle - almost zero recoil.

 

[HPLLC]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

Did you try fitting your mount using the wooden dowel and lapping method the posters here were talking about?

If the suppressor is not tight that is the most likely cause of erratic POI. Try tightening the can and then attempting to loosen it without unlatching the ratchet latch, now check for wobble. Wobble doesn't promote accuracy or consistency. The bolt gun looks awesome, but QD carbine suppressors may not be the best fit for precision rifle applications.

Parallax might be another contributor. <No attempt to insinuate you didn't isolate parallax. Groups 1-3 shifting like that are just odd. Groups 3 and 4 are consistent. (accounting for your elevation change).

If parallax is good and this cyclically repeats itself, that would imply the FH might be warming up and tightening fit (via either the collar or the gas ring fit, or both), and then cooling and loosening fit slightly. Metal expands when heated. I doubt the barrel has anything to do with it.

 

[JSTARSZ]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

The mount and Suppressor are tight. After I read the wobble thread I checked the tightness with the suppressor on the mount and it is tight; as there is not wobble detected. This happens every time I am out. I can almost put the targets on top of each other and they will look the same. As the barrel heats up I get the drop then I get an erratic series. I then try a couple of more sets as the barrel is heated and it settles in. The good thing is I have seen it so much I can almost manipulate the elevation and windage based on previous events. The first shot is 1 MOA left but on elevation par - the second shot will be 1 MOA down and then the third will drop to 2 MOA down.

It is just strange but seems to be repeatable but future tests will enlighten me more. I am going to start to manipulate the elevation and windage as i work through it to see if i am correct. If i can keep it on the paster I guess I am correct.

 

[KYS]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

Could be your powder and ammo combination. I would try some factory match ammo and see what it does. My 223 bolt gun wears the M4-1000 and its a tac driver.

Eliminate all possibilities that you can

 

[JSTARSZ]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KYS338</div><div class="ubbcode-body">Could be your powder and ammo combination. I would try some factory match ammo and see what it does. My 223 bolt gun wears the M4-1000 and its a tac driver.

Eliminate all possibilities that you can</div></div> I will also give that a try too as to eliminate all possible issues.

 

[c4xplsv]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

off topic - i like the cammo pattern on your A5. very nice

 

[JSTARSZ]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: c4xplsv</div><div class="ubbcode-body">off topic - i like the camo pattern on your A5. very nice</div></div> thanks - it is actually the Manner's T2 with Urban Camo Pattern and mini-chassis mag system. I took the rifle out again today and really twisted hard to get the suppressor on tight with the QD mount. The rifle was 1/2 MOA low and correct on windage. So I added the elevation and decimated a 1 MOA dot with five rounds. I loosened it a tad to get it to wiggle and it dropped the rounds 2 MOA low and right so I twisted it hard again to get it tight and back to the center. The wiggle is the issue but I have found on this particular mount if I tighten it the last little bit hard it will not wiggle at all. Thanks for the input fellas it helped immensely.

The more I shoot this rifle the more I like it. Mark Gordon sure makes a nice rifle with that Bartlein barrel - awesome stick.

 

[SymteX]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

That stick is sick....

 

[KYS]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

Mine loves the 75gr Hornady TAP for factory ammo. I've killed many a groundhog and coyote with it. Get a box of that if you can find it and see what it does for you then. I'm not sure if I overlooked it but are you using the brake or flash hider adapter?

 

[shoepop]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

Which adapter brake or flash suppressor? I had the same problem with same can using brake it went away when I changed to suppressor mount.

 

[cruizer]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

tell me about the mat you are shooting off of.

 

[c4xplsv]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

Well in that case... I like the pattern on the T2

 

[KYS]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Mark S</div><div class="ubbcode-body">Which adapter brake or flash suppressor? I had the same problem with same can using brake it went away when I changed to suppressor mount. </div></div>

The brake is a suppressor mount.
The flash hider is also known as the Blackout.
There is also the BrakeOut, that is new to the market.


You have to be a little more specific with what your using.

 

[JSTARSZ]

Re: Bolt Rifle 223 AAC M4/2000 With Bartlein Barrel

the mat is Israeli and I have had friends that have looked for another one for years never to find it again. I bought it back in the 90's at a gun show in Dallas and have never seen it since.