Rounds riding too high in AICS mag

[Gil P.]

My 6.5x47 rounds are riding too high for my action. The bolt really takes some force to move fore aft while may is inserted with rounds in it?

Is it best to file the mag catch ledge on the mag so it rides lower?

The problem with the AICS mag riding too high was in a BAT TR action that is cut for AW mags. There were no issues with the rem 700 action that was in the Sentinel before.

 

[usafa77]

Have you tried adjusting the feed lips?

 

[Gil P.]

Not yet.
Are you saying I should bend the lips inward towards each other?

The bolt rubs pretty hard on the round on top of the mag.

 

[Mordamer]

What action? Is the bolt rubbing on the feed lips? Does it cycle smoothly with an empty mag?

If the bolt is not rubbing on the feed lips of the magazine then it is not likely that the cause is "rounds sitting too high".

Are there big scratches in the brass after you feed a round into the chamber that are caused by the feed lips having sharp edges and digging into the brass?

 

[Gee Kay]

 

[Gee Kay]

and

 

[linedrive301ft]

Gil,
What stock or chassis are you using? I had this issue with a MPA chassis and the mag latch filing was the fix.

 

[Gil P.]

What action? Is the bolt rubbing on the feed lips? Does it cycle smoothly with an empty mag?

If the bolt is not rubbing on the feed lips of the magazine then it is not likely that the cause is "rounds sitting too high".

Are there big scratches in the brass after you feed a round into the chamber that are caused by the feed lips having sharp edges and digging into the brass?

BAT TR
Bolt rubs on brass hard, AND rubs on feed lips.
This action is cut for AW mags if that means anything.
No big scratches on brass from the feed lips, but there are rub marks on the brass from the bolt.
One magazine feeds easier than the other, and rubs on the feed lips less than the other.

 

[Gil P.]

Gil,
What stock or chassis are you using? I had this issue with a MPA chassis and the mag latch filing was the fix.

I'm using a KMW Sentinel with the IMB.

 

[Gil P.]

Gil,
What stock or chassis are you using? I had this issue with a MPA chassis and the mag latch filing was the fix.

The BAT action I'm using is cut for AW mags, would switching to those fix the problem? I've never used them, but they look like they sit lower in the action than the AICS mags.

 

[Gee Kay]

there is a difference in mag design between the 2

 

[MarinePMI]

The mag notch is also different between the two. Your action AND chassis/stock need to both be set up for AW mags if that is what you want to run.

 

[Steel head]

The mag notch is also different between the two. Your action AND chassis/stock need to both be set up for AW mags if that is what you want to run.

This.
Mag catch set up for AW mags holds AICS mags a bit high
Magazine is probably just fine, Your setup isn’t right for it.

 

[Gil P.]

What action? Is the bolt rubbing on the feed lips? Does it cycle smoothly with an empty mag?

If the bolt is not rubbing on the feed lips of the magazine then it is not likely that the cause is "rounds sitting too high".

Are there big scratches in the brass after you feed a round into the chamber that are caused by the feed lips having sharp edges and digging into the brass?

Yes the bolt is rubbing on the feed lips, my last post was incorrect.

 

[Gil P.]

The mag notch is also different between the two. Your action AND chassis/stock need to both be set up for AW mags if that is what you want to run.

I see, what needs to be modded on the stock?
The feed lips themselves actually do rub on the bottom of the bolt when the mag is empty.

 

[Steel head]

I see, what needs to be modded on the stock?
The feed lips themselves actually do rub on the bottom of the bolt when the mag is empty.

File the mag catch down.
Personally I’d just run AW mags or buy another mag catch and modify that if needed so you could swap catch’s depending on mags.

 

[Gil P.]

File the mag catch down.
Personally I’d just run AW mags or buy another mag catch and modify that if needed so you could swap catch’s depending on mags.

I think I may file the mag catch on one of my mags so at least I'll have something I can use while I wait for AW mags.

There shouldn't be an issue using AW mags?

 

[Steel head]

I think I may file the mag catch on one of my mags so at least I'll have something I can use while I wait for AW mags.

There shouldn't be an issue using AW mags?

Probably not if your having issues with AICS mags.
If the AICS mags worked you’d probably be having issues with AW mags.
The issues with modification to the mags is as you cut the the notch down you also reduce protrusion and that brings its own issues but you could probably just gorilla it out a bit with screwdriver if your mag starts dropping out.

Do a search here.
There was an awesome thread on this like 7-8 years ago.

 

[MarinePMI]

Was your sentinel stock set up for AW mags?

@Terry Cross

 

[Steel head]

Was your sentinel stock set up for AW mags?

@Terry Cross

If it was You could just get at reg catch from Terry.

 

[Gil P.]

If it was You could just get at reg catch from Terry.

I'm really not sure. When I bought it from him, I didn't specify a mag catch.
I'll send him an email and find out.

 

[Gil P.]

He hasn't gotten back to me yet, but I do have a newer version of the KMW bottom metal sitting in a box.

It looks like the latch on that one is 70 thou shorter than the one I'm currently using. I'll install it when I get home in about 12 hours and see what happens.

 

[Steel head]

He hasn't gotten back to me yet, but I do have a newer version of the KMW bottom metal sitting in a box.

It looks like the latch on that one is 70 thou shorter than the one I'm currently using. I'll install it when I get home in about 12 hours and see what happens.

That shorter latch should be GTG

 

[Gil P.]

That shorter latch should be GTG

I hope it does work. I still want to try aw mags, it sounds like there is a good chance they'll work with the longer latch.

 

[Steel head]

I hope it does work. I still want to try aw mags, it sounds like there is a good chance they'll work with the longer latch.

There was a really good thread on this years ago with measurements, you might be able to find it.

 

[Gil P.]

There was a really good thread on this years ago with measurements, you might be able to find it.

Thank you ill be sure to look for it.

Terry did get back to me, he said he designs his latches on the long end of the spectrum so that they will work with AW mags in compatible actions and also work with 75-80% of actions that use AICS mags without modification. He also offered to help me shorten the latch. Terry really is a stand up guy, great products and service.

This is perfect for me since I want to use AW mags,and happen to have a shorter latch.

 

[Gil P.]

I measured the latches and they are almost the same size, within a few thousandths of each other. It was dark when I measured this morning, I must have had my calipers on a piece of the bottom metal.

Anyway, instead of filing the catch, I'm ordering AW mags.

 

[Gil P.]

So I got an AW mag, but it won't lock into the bottom metal. Would filing the mag latch shorter allow the mag to lock into place?

I can't imagine how a longer latch would help.

 

[MarinePMI]

Since you've got two latches already, yes, file one down to fit the AW mags.

 

[Gil P.]

Since you've got two latches already, yes, file one down to fit the AW mags.

Thank you, it might even make both mags fit better since the aics mags are riding too high.

 

[308pirate]

This is unrelated to the problem but it makes me wonder why AI didn't just standardize on the AW magazine for everything including their chassis system.

The Remington 700 and just about anything loosely based on the Mauser 98 action was designed with a dual column internal magazine so feeding from an AW magazine located correctly should be the easiest thing to do.

 

[morganlamprecht]

Thank you, it might even make both mags fit better since the aics mags are riding too high.

only file it just enough to latch it and work slow...with AWs in a 2 lug you need them high and tight

 

[Gil P.]

Got it, I'll go in 10 thou increments. The mag fully inserted (though not latched) does rub on the bolt body.

 

[Gil P.]

This is unrelated to the problem but it makes me wonder why AI didn't just standardize on the AW magazine for everything including their chassis system.

The Remington 700 and just about anything loosely based on the Mauser 98 action was designed with a dual column internal magazine so feeding from an AW magazine located correctly should be the easiest thing to do.

Maybe their action dimensions are different? I've never owned an AI, but it seems like there are lots of different actions that take different magazines.

 

[morganlamprecht]

Got it, I'll go in 10 thou increments. The mag fully inserted (though not latched) does rub on the bolt body.

what part of the mag rubs? the follower should rub with no rounds in it...the mag lips shouldnt rub ever and the cut on the action shouldnt even allow that to happen if it was cut correctly

 

[Gil P.]

what part of the mag rubs? the follower should rub with no rounds in it...the mag lips shouldnt rub ever and the cut on the action shouldnt even allow that to happen if it was cut correctly

I'll check it after work today.

 

[Steel head]

Maybe their action dimensions are different? I've never owned an AI, but it seems like there are lots of different actions that take different magazines.

Same magazines but chassis/stock differences and action differences add up to a bit if fitting at times.

 

[Gil P.]

what part of the mag rubs? the follower should rub with no rounds in it...the mag lips shouldnt rub ever and the cut on the action shouldnt even allow that to happen if it was cut correctly

You were right, only the follower rubs. I took about 15 thou off, but it's still not locking in. I'll take off a other 15 thou and see what happens.

 

[morganlamprecht]

on all my AWs i cut a small bevel on the rear side of the follower so the bolt slides over it easily if i ever need to single feed a round fast, i can toss it in and run the bolt without it hanging up on the follower

not sure if that was by design as a "empty mag indicator" or not, but im not a fan lol

 

[Gil P.]

I got the AW mag to lock in, but now I'm having a feeding problem.

Some rounds will get pushed into the action and won't feed unless I really force it. When I play with the follower and angle the rounds a little nose up, they feed fine. When I unload a magazine by hand, the rounds move in a straight line, they don't nose themselves up or down are the supposed to?

Rounds seated to rear of mag.

 

[Gil P.]

One more thing I should mention

The AW mag does have some side to side play, I think this may be by design however. Fully loaded AICS mags have zero play.

Moving the magazine from one side to the other when a round doesn't want to feed doesn't help it feed.

 

[1fliride]

Not yet.
Are you saying I should bend the lips inward towards each other?

The bolt rubs pretty hard on the round on top of the mag.

Yes, bending the feed lips in will remedy this issue. MPA makes a tool for this.

 

[Gil P.]

Yes, bending the feed lips in will remedy this issue. MPA makes a tool for this.

I havent tried it yet, but will probably just try to make a tool.

Bending the feedlips inward will move the rounds slightly toward the center of the magazine? I'm shooting 6.5x47.

 

[Gil P.]

Well, I bent them inward.

Front measure 593 thou
Rear lips measure 597 thou

The front lips started at 627 thou.

The bullet tip is still catching on the side of the action, and I notice when I try to slide the rounds out by hand, the shoulder on the neck / bullet junction catches on the front of the magazine.

When I adjusted the lips where the front was much narrower than the rear, the bolt would skip over some of the rounds and not pick them up.

Any suggestions?