.223 Nuke

[meestermeetch]

I have a first generation ARC nucleus. I shot the first barrel out (~2500 rounds of 6.5 creed) and got a new .223 Wylde barrel and bolt head. Everything headspaces and seems to to be good to go, mounted in a KRG bravo with an enclosed forend.

I have a metal accurate mag and a polymer MDT mag. I can’t seem to get through a full mag without and issue.

Early in the mag the round come up but dont go into the bolts controlled round feed so it gets jammed into the feed ramp.

In the middle of mag, I get around going funky and finding a corner someplace typically vertical above the bore.

Both of these require dropping the mag.

At the end of the magazine the mag seems to drop and the bolt rides over the cartridge. A smack to the mag fixes this but less than ideal.

Which problem I have is unpredictable. One of the metal mags seems to be the favorite but I thats not 100% and neither is changing to one of the other stocks I have one hand. I didn’t have to tinker with this action/chassis combo when I was shooting 6.5, and it didn’t care about what mag I used…. Running the action fast helps particularly with ejection but otherwise I am frustrated.

My goal of this rifle is an inexpensive PRS trainer and a fun gun for club matches/loaner rifle for days when it isn’t windy. So feeding is crucial, and I think it makes even a prone range day more fun.

Any help is appreciated.

Thank you
MM

 

[bbhank]

I had the same issue with a KRG bravo and a Howa chassis. My issue was not enough tension on the back of the follower which made the base of round dive into the mag and then it was anyones guess where the bullet would get jamb depending on how many rounds were in it.

If your accurate mag has the flat wide spring in it. Open it up and the open up the bends on the front side just a tiny bit. This should increase the tension on the back of the follower and hopefully resolve your problem.

As info I tried tweaking the feed lips no help. Then I bought a long mag catch and hand fitted it and this provided some relief but only reduced my FTF's by 25%. Then I tried a AICS mag, no change. Lastly i did the spring mod as precscribed by accurate and now flawless feeding!

Good Luck!!!

 

[meestermeetch]

Ok, so a friend came over as nf brought his magpul pro chassis and a manners with a mini chassis in it. Both fed 100%, so is this a chassis issue? If so how do I resolve it?

 

[Rob01]

Seems like a chassis issue. Have you tried pushing up slightly on the mag and see if it helps the feeding? Sometimes it's mag height/placement that would cause these. You might be able to work around it if you can find it is a mag height issue.

 

[srt-4_uk]

Try to loosen trigger guard screw and move trigger guard forward to get the mag to fit tighter. Sounds like a loose fit making the mag drop a little.

 

[meestermeetch]

Ok so for anyone out there following this, I stripped my KRG down to the backbone and reassembled, by tightening the bolt behind the action that is accessed from the top at the end as you are supposed to, I got it to feed 100% from the accurate mag. However was still having bolt override on the MDT poly mag, and when it didn’t over ride it didn’t reliably control the round….
Unclear what my MDT issue is, but reading the instructions on the KRG solved a lot of my problems.
If anyone has any ideas on fixing the MDT issues, please let me know.

 

[B_w.]

I think you can get a few different length mag catches from MDT to raise it up a bit.

 

[srt-4_uk]

I think you can get a few different length mag catches from MDT to raise it up a bit.

I don think that's going to help is KRG chassis though...