FTF - bolt catches magazine

[GarandFan]

Hoping someone's experienced this before...and knows potential solutions.

I just finished two Romy G kits on bent-up AK builder flats. All is well on both rifles, excepting a little bolt-canting in one rifle.

What seems to happen is that the bolt sometimes cants clockwise in the bolt carrier. This causes the squared-off bottom piece (the part that strips the round and travels between the magazine cut-out) to cant clockwise (to the left) where it catches on the left magazine feed-lip.

Now, all I can figure is that this might becaused by two possibilities (or both together):

1) Left rail is too high. This would cause the bolt's locking lug to be pushed upward, resulting in the bolt canting clockwise. This does not seem the case to me.

2) Right rail is too low. This would cause the right side of the bolt (underside surface of the upper guide lug) to ride too low, resulting in the bolt canting clockwise.

Both rails were installed using drill bits as spacers. I used a 1/4 and a 17/64 bit...and the rails seem to line up fine with the trunnion cutouts. I am a little perplexed, but am a relatively new builder.

Other than filing down all my mags (which is a very poor option), I am tempted to try bending the right rail upwards just ever so slightly. Alternatively, I've considered machining the bolt under-face (the part that strips the round) a little to allow more clearance.

Any ideas Gents? Thanks in advance.

[ronin]

Just to check one thing - did you forget the selector stop that goes between the triggerguard and the receiver? If so, that not being in would cause the magazine to be pushed up higher.

I've never had the bolt cant around. Did you use drill bits (or something else) as a spacer to ensure the lower rails were perendicular to the upper rails and correctly gapped?

[Ding]

did you use those predrilled rails? also like ronin asked,selector stop plate installed?maybe one rail is warped from heat treat,check for that.

[GarandFan]

Thanks for the quick replies. The selector stop is inserted properly between receiver and trigger guard. I used drill bits to ensure correct spacing between inner and upper rails...1/4" on one side and 17/64" on the other (I think the 1/4 was on the left...but can't remember for sure...I would have to look at them and they are not in front of me).

I used AK builder flats, rails, center-support pins and collars, and rivets. The rails are not heat-treated and not pre-drilled. On one rifle I clamped rails, drilled, set center support, then welded. On the other I clamped and welded rails, then drilled and set center support. Both receivers were heat-treated at axis pin holes and ejector tip. Even now, the drill bits fit nicely in place so that is why I am a little befuddled at why this bolt is turning/canting a little on that one rifle.

Thanks for the continued ideas. These were my very first bent receiver builds. 100% receivers are way easier, but I love to learn and do and am glad that you'll share your collective experiences.

[allesennogwat]

Make sure the receiver isn't pinched in at the center support. Make sure the ejector tip clears the bolt and isn't pushing it sideways. If the receiver bottom is bent upward where the trigger guard rivets are it might be too high and too close to the bolt.

[Ding]

check for receiver warpage,could be warped from axis pin holes being treated.bout the only thing I can think of that would mis align rails right now.also check the receiver where the trigger guard mounts for flatness,sometimes it can be outa round from being put through the jig.might be too far up into receiver which will raise your mag well..just a thought.

[motorhead]

look up through the magwell and see if the ejector is pushing the bolt over. iirc the tip should be .560 from o/s rec. side.

[GarandFan]

Thanks again. I will check all this stuff out. It could be that the ejector tip is pushing against the bolt...

The mag-stabilizer rails (lowest rails) need a lot of trimming to allow mag to fit. Are those rails made for 5.45 AKs? If so, I might need to trim back the ejector tip....it seemed to fit pretty well so i left that alone.

Thanks again.

[sw44]

The ejector and the mag stabilizer rails both need to be trimmed on the rails supplied with AKBuilder flats. They are sized for the 5.45x39 rifle. Trim the ejector back so that it just clears the interior of the bolt slot and you should be fine.

[Ding]

the rails come made for the 5.45 but need to be trimmed alot for the 7.62.I do the major trim BEFORE I lay the rails in and then trim with the dremel to fit after welded in.sometimes the 5.45 fit(ejector tip) needs a slight bump to fit but the 7.62 needs a good hit(ejector tip)don't understand something,if your lower rails aren't trimmed how is the mag being hit?

[GarandFan]

Sorry I was unclear about the lower rail trimming. I have trimmed the lower rails (mag stabilizers) and the mags fit just fine. It's just that on one of the rifles, the bolt cants clockwise and strikes the left-hand feed lip of the magazine, stopping the bolt and carrier cold. The ejector does clear the bolt...but just barely. Yes these are AK builder rails and no I have not trimmed the ejector on either of them. Will look at it again to see if there is any contact and will trip ejector accordingly.

[ronin]

All of his ejectors are sized for 5.45 so you do need to trim them back carefully (it's easier to take off metal than to add it back). I size each ejector by hand and go for the ejector to just nudgle the bolt as it goes by. If you take off to much and the bolt can pass without the ejector engaging the shell case then you'll have failures to eject.