Gunsmithing Feeding Issues

[optimist]

Can anyone tell me how to tune my AICS mags to feed more consistently? I get this weird hang up, like the round pops up to soon or something as I'm trying to chamber it. I have to then take a little pressure off the bolt and then it free's itself and I can put it home. Am I going to slow on my throw, or do I need to get the rounds to release earlier or later from the mag, by modifying the feed lips? I'd appreciate any guidance here.

Savage action .260 Remington, XLR chassis.

 

[SONIC SAAMI]

Re: Feeding Issues

This is an easy fix.

Make up 5 dummy rounds.
Look into the port and work the action to see just what is hanging up the round.
Adjust the feed lips as necessary.

H-S PRECISION makes a tool that Brownells sells for adjusting the feed lips,but you can use a pair of pliers.
It also may help to smooth the inside edge of the feed lips with emery cloth.

 

[optimist]

Re: Feeding Issues

Thanks DaveD. I have tried that already and have smoothed out the inside edges of the feed lips. I guess I'm still wondering, how do I know if I have to open up or close the feed lips? What condition indicates widening vs. narrowing? My first instinct is to open up the feed lips to get the rounds a bit higher, I'm not sure if that's right though.

 

[ds03cobra]

Re: Feeding Issues

I had this same issue with my XLR CHASSIS FN PBR . I figured out if i push up on the magazine while cycling the bolt the rounds would feed fine talked with Kyle determined the mag catch was too short sent chassis back to kyle made the mag lever a touch longer no more issues not saying this is your problem but you could give it a try

 

[SONIC SAAMI]

Re: Feeding Issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Optimist</div><div class="ubbcode-body">Thanks DaveD. I have tried that already and have smoothed out the inside edges of the feed lips. I guess I'm still wondering, how do I know if I have to open up or close the feed lips? What condition indicates widening vs. narrowing? My first instinct is to open up the feed lips to get the rounds a bit higher, I'm not sure if that's right though.

</div></div>
I would play with the rifle and mags see what it needs.

 

[optimist]

Re: Feeding Issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ds03cobra</div><div class="ubbcode-body">I had this same issue with my XLR CHASSIS FN PBR . I figured out if i push up on the magazine while cycling the bolt the rounds would feed fine talked with Kyle determined the mag catch was too short sent chassis back to kyle made the mag lever a touch longer no more issues not saying this is your problem but you could give it a try </div></div>

Thanks for the idea. I think that could be an issue. I dont' want to send it back, being in Canada, and Kyle at XLR is a dude, he's been very decent to deal with. I will ask Kyle if he can make me a up a slightly longer catch and send it up.

 

[2156SMK]

Re: Feeding Issues

The check for mag catch length is how much the mags move up and down in the gun when an empty mag is latched in place with the bolt closed.
You only NEED about 0.020" or so there.
If you have a LOT more, get a longer mag catch lever.
If you have proper clearance, then open up the mag lips until the bolt nose engages enough of the case that it is ALMOST, but not quite touching the primer.
This should work out to about 1/8" of overlap between the bolt nose and the cartridge in the top of the mag.
This should be done with the mag hanging against the bolt catch, not being pushed up into the gun.

After you get the rear of the case up enough, widen the front of the mag lips enough that the cartridge is sitting level or even slightly nose-up.
This will ensure that the bullet tip catches the feed ramp as you push the cartridge out of the mag and into the action.

 

[optimist]

Re: Feeding Issues

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 2156SMK</div><div class="ubbcode-body">The check for mag catch length is how much the mags move up and down in the gun when an empty mag is latched in place with the bolt closed.
You only NEED about 0.020" or so there.
If you have a LOT more, get a longer mag catch lever.
If you have proper clearance, then open up the mag lips until the bolt nose engages enough of the case that it is ALMOST, but not quite touching the primer.
This should work out to about 1/8" of overlap between the bolt nose and the cartridge in the top of the mag.
This should be done with the mag hanging against the bolt catch, not being pushed up into the gun.

After you get the rear of the case up enough, widen the front of the mag lips enough that the cartridge is sitting level or even slightly nose-up.
This will ensure that the bullet tip catches the feed ramp as you push the cartridge out of the mag and into the action. </div></div>

Thank You! That's what I was looking for. I will work on that today, thanks for the detailed advice. Dan

 

[jrpilot]

tag good info

 

[Sonic Crack]

Also look at the cross pin hole for the bolt head. It will have a sharp edge that can catch the case head/scratch brass. Might be catching the round below in the mag, pushing it forward in the mag causing problems.

 

[devldogs55]

You know what completely solved my exact same problem with my XLR chassis ?? Making sure to torque the chassis to the action to spec. Seriously - I could hardly chamber the first 3 rounds. I played with the lips and it made it slightly easier - then I tightened the screws and it was night and day different.

 

[LRI]

Occassionally we have to deal with this.

The solution at times is to look closely at the breech chamfer. If the cartridge hangs up on the breech edge it can create the same problem. Widening the chamfer a pinch more often makes it go away.

The other issue can be the amount of case overlap you have with the bolt face. If the outer edge of the rim isn't invading the inner ring of the bolt face by a bit it alters the entry angle into the breech/chamber. Less overlap means a more aggressive entry angle and this is when problems surface.

You can bend up feedlips, but in this case the real solution is to get the floor metal sunk further into the stock to get the magazine to invade the magazine mortise feature on the bottom of the action.

Often times is at the expense of presentation. The floor metal can end up sunk into the stock which looks like ass. When this happens I pull the release lever and TIG weld a bead of air hardening rod on the edge. Then its just a matter of shaping it on a benchtop belt sander so that it works again.

Easy fix this way, takes about 10 minutes to do. Some release levers are AL. My TIG skills on AL sux the egg so in that case I end up making the release from scratch. The CDI ones were (are?) aluminum and I did this every time. I don't use them at all anymore just for this reason. Too many other good ones out there that are made from steel.

AL isn't the material for this IMO because the magazines eat it over time and then it starts acting stupid due to burrs and stuff.


Good luck.

C.