Mags sticking

[muddiver8]

I bought my evo to shoot Uspsa PCC class.  Before I shot the gun the mags dropped free.  I shot about 100 rounds.  now the mags don't drop free, I have to pull them out. I cleaned all the gun with no change.  Doing some looking at the trigger group, the slide release that holds the bolt open on last round is holding up the mag from dropping free.  if I push the mag release and push down on the slide release the mag shoots out.  Any ideas or anyone else have this problem?

[Destructo6]

Bolt forward or bolt back? If the bolt is back, was it locked by the empty mag bolt hold open or the charging handle?

[Sigma05]

I have the exact same issue when bolt is locked back from empty mag, it won't drop freely. Will investigate and get back to you on it.



"Ex Umbris Venimus"

[Sigma05]

Found out what the problem is. If you look at the back of the mag, where the pin that locks the bolt release lever up is, you will see a slot in the mag. When the bolt rests on the release lever, it pushes it forward, and the tab goes into that slot. Only solution I can see is rounding off the edges of both the slot in the mag as well as the tab on the bolt release lever. Does that make sense or do you need pics? 



"Ex Umbris Venimus"

[dapakattack]

Pics are always helpful!

[Sigma05]

The tab that the magazine pushes up on the bolt release lever can be seen in this pic clearly.



That tab gets pushed into the slot that's recessed in the mag, on the left of the follower pin. You can clearly see it in pic. When the bolt rests on the release lever, it pushes it forward into that recessed slot and retains the mag from dropping freely. The rest of the time, full mag or when bolt is locked open using the charging  handle, there is no forward pressure on the bolt release, so it's backed out of the recessed slot, and mag drops freely.  Makes sense??



"Ex Umbris Venimus"

[muddiver8]

I was thinking the same thing that the tab that pushes the slide lock up is catching on the mag.  looks like there will be some work on the tab till it drops free.

[Destructo6]

I'm thinking more along the line that when the bolt is locked back with the charging handle, the spring that pushes the bolt release down also pushes the magazine out of the magwell via that little tab on the back of the magazine. This is the, "hey, it pops out freely" mode. So, not only gravity pulling, but spring pressure is pushing the magazine out of the well.

When the bolt is locked back by the bolt hold open/bolt release, that little spring on the bolt release is out of the picture, making gravity the only force acting on the magazine, which may or may not stick.

Remove your trigger group/magwell out of the gun and bench test it. With magazine inserted, hit the release and watch the bolt catch drop with the magazine. Then, hold the bolt catch up (as though it is engaged with the bolt) and hit the magazine release. You may find that it sticks just like it does in the gun.

I did some light sanding on the front flat part of one of my 20s and it seems to fall a little easier than before. I think the light weight of the 20s and a little bit of friction keeps them from falling freely. If you do the mag flick maneuver, they come right out. I wonder if adding a little weight to the base plate would help...

[muddiver8]

I am surprised no one has made an aluminum basepad yet.  I think the extra weight of the aluminum would help.   Dawson precision, Taran Tactical or MBX would be good

[OhHey1]

I am surprised no one has made an aluminum basepad yet.  I think the extra weight of the aluminum would help.   Dawson precision, Taran Tactical or MBX would be good

They've been out so long that they're on sale right now...

http://czcustom.com/cz-scorpion-evo-3-s1/cz-evo-scorpion-base-pad.html

[Sigma05]

I did some light sanding on the front flat part of one of my 20s and it seems to fall a little easier than before. I think the light weight of the 20s and a little bit of friction keeps them from falling freely. If you do the mag flick maneuver, they come right out. I wonder if adding a little weight to the base plate would help...

You have any pics of where you sanded? Have you tried it at the range, after the sanding, and where there any feeding issues?

 I'm going to try something different but want to have another option if that doesn't work.

[Destructo6]

You have any pics of where you sanded? Have you tried it at the range, after the sanding, and where there any feeding issues?

At the top/front of the magazine, there is a section that is a little higher than the rest of the rib on the front of the magazine. It looks like a vertically oriented rectangle. This is where I sanded and not much at that. No feed issues, but the benefit is pretty questionable.

I still think adding weight to the baseplate is worth investigating.

[Sigma05]

Thanks. I have the aluminum pads and they don't make any difference without modifying anything.



"Ex Umbris Venimus"

[czevo]

Any further info on this?  Have the factory 20s.  Mags flew out at home with ease but first trip to the range last night and once the evo was hot they would stick every time. Thanks!!