Bush Master Carbon 15

[bowyer19]

I was reading a thread on the Carbon 15 which seemed to be out of date but had some unanswered questions that maybe I can help with .I just purchased one before Christmas. Mine has a forward assist,dust cover and shell deflector;which apparently ealier models did not have.

At first accuracy appeared to be dismal-4-5" groups @100yds. bench rested.I had heard a person should not really worry about the accuracy in chrome lined barrels until at least 100 rounds had been put through them. I now have about 200 rounds though it, almost all with American Eagle 55gr.FMJ. The last bench session produced consistent 3-4" groups at 200 yds. 200 yds. is not a typo. I know that is not sterling accuracy however I consider it not bad for a light weight,16" barreled carbine shooting in-expensive bulk ammo.( All groups are 5 shot).I have had no malfunctions at all.

My only disappointment so far is Bushmaster tells me I cannot put one of their 6.8SPC uppers on the carbon lower;which I thought would make a great timber deer rifle.

I don't know if this is typical performance for current Carbon 15's but hope this is helpful.

 

[BushyGuy]

thats not too bad, my Bushy gets 3-4" groups at 100 yards cuz i have a short barrel 11.5" with 5.5" flash hider. i might get a 16 inch upper later for my Bushy.

at 25 yards i get 1/2- 1" groups it gets larger as i go out farther from the target.

 

[bowyer19]

I really need to try some better loads but I can't say I'm unhappy.

 

[Chopdoktor]

Your short AR barrel has nothing to do with accuracy. It has to do with velocity. An 11.5" barrel will be as accurate as a 20" barrel, but it will have much less velocity. In fact, the shorter barrel will be more consistent because a shorter barrel is stiffer and flexes less during firing. This has all been covered plenty on here before, I'm sure, but I just wanted to rectify that common misconception. I've gotten 1 moa out of 11.5", 14.5", 16" and 20" barrels, all on the same lower AR receiver, using the same loads of ammo.

 

[bowyer19]

I don't expect in-accuracy because of barrel length but because of the lightness of the barrel;especially with a long string of fire. The ammo is probably not the most accurate in the world also.I am amazed at how cool that thin barrel does seem to remain. Most of my hunting rifles would not let you hold on to the barrel after a five shot string-unless you have a high tolerance for pain.

 

[bowyer19]

A better trigger would also be a big help.The stock trigger is definitely not the worst (not as bad as a Ruger mini-30 I had) but definitely needs to be replaced some day.

 

[Chopdoktor]

I highly recommend the Rock River 2-stage 3.5lb trigger. It's around $105, and it's absolutely amazing.

 

[bowyer19]

Thanks, I had heard there is a good trigger for around $100.

 

[Chopdoktor]

I get mine from Valhalla Tactical. You have to pay $5 extra for the 3.5lb extra-light trigger, but it's worth it, for sure. I don't have to worry about light primer strikes, either, even with cheap ammo. It's a great setup for a very fair price.

 

[bowyer19]

One more thing: I just tried a standard aluminum upper on my carbon and it fit perfectly.Since the carbon is actually supposed to be 40% stronger ; does anyone no why the 6.8 will not work. I asked B.M. but it has been several days with no answer.

 

[45Autoloader]

Keeps us posted on the 6.8 question and any update you make to the trigger, Bowyer19.

I have one on back order from my local gun store.

Does the Carbon 15 have a metal insert in the feed ramp?

 

[bowyer19]

It doesn't appear to have metal on the feed ramp.

 

[bowyer19]

I looked at it again. It appears it may be a coated steel insert. Whatever it is made of, it is extremely hard.

 

[bowyer19]

Went ahead and bought a 6.8 upper (Bushmaster,sp2,16",4 groove) . Everything seems fine except for one thing,no 6.8 ammo in the whole area;so I have been unable to shoot it. Ordered some ammo from SSA but they are out of brass. Also case trimmers;etc seem to be hard to get.RCBS lists dies but Lee does not list a shell holder for their capper.It appears ammo availability may be a draw back at present.

 

[Dr.Rob]

I'm moving this to rifles, this forum is meant for historical research etc. This is more of a technical query...

 

[bowyer19]

Finally got some ammo:SSA 110gr.Pro Hunter and TSX both TAC. Had mounted a Burris 2X7 fullfield and finally got to sight in. Weather was crappy but got sighted with the PH. Functioned perfectly and 1.6" group @ 100 YDS with PH. Will probably do better when shot in and under better weather conditions.(Spitting snow@10mph switchey wind.)

 

[bowyer19]

Finally had a chance to try the 6.8 upper @ 200yds -same crappy weather as first time.We did not set up a really good sandbagged rest but were resting over my shooting bag. Because of the weather we only fired three three shot groups. All were a shade under 3". If this is like my other barrel it will get better after more rounds have gone through it. Properly sand bagged under good conditions I think it may very well hold under an inch. Since 1.5" three shot groups @100yds. were considered the gold standard for many years with 5 shot groups @ 100yds the military acceptance standards back in '66, I consider this accuracy excellent from a light weight carbine barrel.It is certainly "minute of deer heart".

 

[bowyer19]

Military acceptance was 3" five shot group at 100 yds. if I remember correctly.

 

[Damon555]

http://www.thehighroad.org/showthread.php?t=588686&highlight=carbon+15

 

[bowyer19]

'Had a problem with two "slam fires" with SSA 110 gr.Sierra Pro Hunter tactical ammo with CCI #400 primers (according to SSA they are going back to Mil Spec primers). Changed to heavy buffer at SSA's recommendation and titanium fire pin at Bush Master's. Did both at the same time. No more "slam fires" .

 

[taliv]

you might want to pm member 'slamfire' as i believe he is keeping a history of slam fires