[Russell92]

So I'm trying to install an Ed Brown extended mag release in my 9mm STI Trojan. First the diameter of the button was too large and wouldn't fit into the frame so I had to sand that down. Now I've got it installed, but when I try to insert a mag it hits the mag release and stops, need to press in on the mag release to get the mag the rest of the way in.

I'm comparing the Ed Brown mag release to the stock STI release and can't tell exactly where I should file down the release to get it to work. I'm trying to see if there's a certain corner or bevel that looks larger on the Ed Brown, but not seeing it so was hoping y'all might have an idea exactly where I should try filing?

In the first pic you'll see the height of the mag release tab is the same on both. And in the second pic it looks like the bevel goes down even further on the Ed Brown release so I'm not sure where's the hang up. (Ed Brown catch on the left in both pics).

Thanks!

 

[BushidoBrown]

Tagging for future reading.

 

[Greg Derr]

Dychem the bevel, locate the impact point, smooth, repeat.

 

[AndyC]

If you don't have Dykem you can use a Sharpie

 

[Infidel525]

You can't see it ? It's as plain as day in your 2nd picture.

 

[BushidoBrown]

You can't see it ? It's as plain as day in your 2nd picture.

I imagine if he 'could see it' he wouldn't have started a thread asking. Perhaps you could be helpful and be more specific?

 

[Russell92]

Thanks BushidoBrown, shockingly no I can't see it, hence the question. If you're talking about the far right side there's a second bevel there, lighting just isn't good in pic, can try to take a better one tonight.

I don't have any of that dychem, but will try something like that. Maybe whiteout would work well for showing the impact point on the catch.

 

[pistolwrench]

I've NEVER had any luck with Ebbie's mag catches.

And yes, I have beveled and polished.

I'm unable to determine where the problem lies.

 

[sevenL4]

Felt tip permanent markers are often used in place of Dykem.

 

[Infidel525]

shockingly no I can't see it, hence the question. If you're talking about the far right side there's a second bevel there, lighting just isn't good in pic, can try to take a better one tonight.

Look at the Arc coming down from the top right under the button you sanded down , that cutout is supposed to be the shape of the mag , it's clearly not , look at the button on the right and compare the 2 , place it against a mag.

My ED B tactical must have dropped right into the crappy Remsport frame I used because there was no fitting or deburring of the parts in bags used in it's assembly ... though someone was nice enough to roll the edge over polishing it for hardchrome ...

I bought an EGW and the right side didn't fit the frame cutout on 2 different frames.

 

[diadem]

I am no way experienced enough to give advice but I had a similar problem with a no name one I got off ebay. I ended up taking the slide off and marking the magazine itself up with a sharpie then inserted the mag while looking down the magwell from the top. A couple of raps on the bottom of the mag left a mark on the mag that I could see. The marks on the catch were too small to even find. Also by switching back and forth between the old and new and looking down the magwell I could see the subtle difference.

 

[BBBBill]

... I bought an EGW and the right side didn't fit the frame cutout on 2 different frames.

Too large to enter the frame? There was a bit of discussion of poorly fitting mag catches here a couple years ago with the desire for slightly oversized ones be made to allow fitting for a close fit to the hole instead of the usual wobbly fit.

 

[bamashooter]

I'm probably the least experienced part fitter here however I have managed to fit 2 magazine catches/ releases.

With the issue you are running into, I first take the known functional one and compare to the other. Even a very small difference, probably the "shelf", will be discernible.

Take the good catch and mate it to the magazine as if the magazine is fully inserted to the pistol. Note where it touches everywhere (right side and curved front) of the magazine.

Do the same with the new catch. You will definitely see where you need to do a little filing / dremeling.

Another tool you can use is either a dark sharpie for a stainless magazine or a silver sharpie for a dark magazine. Sometimes there will be a vertical scratch between the front of the magazine and the catch opening. This too will aide in your determining the area to be worked on the release. And also study the magazine side of the catch which faces the front of the magazine; the elongated section running left to right. I have found those to be all over the place regarding machining. I like to dress that area to pretty much mirror the contour of the front of the magazine. Just go slow, keep fitting a few times and basically what you're doing is evaluating all the contact points. Since you have a known good catch to use as your "truth", you should be just fine.

 

[Russell92]

Success! Well sort of. It's still harder to insert a mag than with the stock mag catch, but it's serviceable. If I insert a mag slowly it still feels pretty hard to push past the catch, but inserting a mag quickly goes right in. I'll try it at a match this weekend; see how it does with a bunch of mag changes and maybe I'll take a bit more off.

I didn't wind up needing to mark up the catch; I was trying various mags inserting them and that left enough of a mark on the catch that I could see where I needed to sand down. First picture below shows where the problem was with the red circle. It's that edge where the two different bevels meet going pretty much the whole length of it.

I sanded a bit at a time, but did cover a larger area than just that little red circle as you'll see.

One thing I noticed with this exended mag catch is that it's pretty easy to press the catch in too far when trying to eject a mag and that can cause the mag to hang up and not drop free. I would have thought they'd build some kind of stop into it to prevent this. Not really a problem for me since I'm a lefty and it's not easy for me to press it in that far so no big deal.

Pictures of finished product below. Hey Ed Brown, nice "drop in" mag catch!

 

[NoExpert]

I didn't see anything in the above, but does the mag drop freely when the catch is pressed in?

 

[jjfitch]

You are comparing two parts that may not be faithful to the original JMB specs. and fallen victim to tolerance stacking. If available test and compare an original JMB mag release. The result may be evident "right there"!

I had to do this fitting a 9mm slide stop. The evidence was "right there"!

All the best,

 

[bamashooter]

Sure would be nice to see these two facing to the left.

 

[Russell92]

Sure would be nice to see these two facing to the left.

Here ya go. I didn't take this pic before since it's the other side that contacts the mag while inserting it. I didn't have to do any filing on this side.

And also here's a pic of the mag release installed for anyone interested. I did a bit more polishing and now mags insert pretty smoothly. Much easier to eject mags with this extended catch for me as a lefty.

 

[jjfitch]

Does the contour of the mag catch match the contour of your mags?

In a previous post I mentioned comparing the offending catch with a JMB original. In looking at the curvature of the mag catch that contacts the front of the mag it looks like the catch may be pushing the mag from the left to the right causing resistance. Lay the catch along the front of a mag and see if the contours match. Looks oddly out of spec.

All the best,

 

[bamashooter]

Thanks for the rotation. Are you beyond satisfied now or is there a bit more tweaking to follow?