Ruger P90 Mags

comn-cents

New member
I just bought an older Ruger p90 with the original 7rd mags. The gun shot like I expected, accurately and 100% reliable. I bought a couple of factory 8rd mags. They just won't work, slide won't lock back on last round. One of them would only load 4 rounds, it seems very unRuger like. So I cleaned the mags and I can get 8rds in both now but still won't lock back on last round. Anyone else have problems matting old gun with new mags?
 

lee n. field

New member
My first thought is, are you sure they are factory magazines? Promag does make aftermarket magazines for the P90/97/345. Factory magazines have a stainless tube and black plastic base with the Ruger phoenix molded in. May or may not have a "this gun can be fired with the magazine out" sticker on the side.

Check the followers. Check the springs, that they are oriented right.

I have 8 factory P90 magazines, a mix of 7 round and 8 rounders, never a problem with any of them.
 

jmr40

New member
I've owned P-90, P97 and the newer 345 and have been able to interchange all the mags between the 3 with no problems. Including the older 7 round mags. You can replace the follower on the 7 round mags and convert them to 8 rounders.

The only problem I ever had, and it sounds a lot like your problem was with one of the 8 round mags for a P-97. Somehow when the magazine was assembled they got "2" followers on top of the mag spring. I had trouble loading it until I found the problem and removed 1 of the followers. Worked great after that and I used the extra follower to convert one of the 7 round mags to 8 rounds.
 

comn-cents

New member
They are Ruger factory mags!
I pulled them apart and only one follower per mag.
Everything seems correct, I think I might just try some wolf springs and think that helps.
Like I said before it is unusual for Ruger factory mags.
 

P97

New member
I have a total of 10 Ruger magazines and have never had a problem with any of them. I did change out the Springs and Followers on some of them, to use the plastic followers. The reason for the plastic followers wasn't related to function. I didn't want the metal ones pinging my P90.
 

Silent Bob

New member
I too have had jamming problems with the Ruger 8-round magazines and much prefer the older 7-round design. I believe most of the problems with the 8-round magazine revolve around the Chip McCormick Devel follower (same as used in Chip McCormick 1911 magazines) and the weaker 8-round spring, which give me the same problems in 1911s.

I have heard of people using Tripp Super-7 upgrade kits to turn the Ruger 8-rounders into reliable 7-round mags and using Wilson 47D conversion kits to have a more reliable 8-rounder, but have never tried any of these. I hunted down a bunch of the older 7-round magazines and just use those. Actually my friend does since I ended up giving him the gun and mags but I still shoot the gun from time to time.
 

Silent Bob

New member
Sorry, I took the phrase that the mags "just won't work" to mean you had jamming problems with them, my mistake. I did have failures to feed with the 8-round mags, and some failures to lock back as well. I also had the slide locking open in the middle of mags, but that was probably me hitting the slide stop with my thumb or something (that was when I was still relativley new to semiautomatics).
 

madmag

New member
I own a P90. Here is the deal.

The 8 round mags are lousy. Several options, but what I did was change the spring out to a normal GI 7 round and the follower to a skirted Wilson Combat part. I first got this idea from the Ruger forum.

Now I have 7+1 mags that work. Yes it is unlike Ruger to have such an error, but many people had this problem with the P90. Did I mention the original P90 follower comes forward out of the mag and hits the frame.:mad:

Remember. P90 mags have the same inside dimensions as any GI mag. The reason you cannot just put in a surplus GI mag. is Ruger made the location of the mag. release notch different to prevent using after market mags.

Silent Bob said:
Ruger 8-rounders into reliable 7-round mags and using Wilson 47D conversion kits

Yes, that works.

PS: Except for the mag issue I consider my P90 and one of the most reliable and accurate semi's I have ever owned.
 
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lee n. field

New member
Remember. P90 mags have the same inside dimensions as any GI mag. The reason you cannot just put in a surplus GI mag. is Ruger made the location of the mag. release notch different to prevent using after market mags.

Not being able to use GI magazines probably cuts down on Ruger having to deal with support problems, with random cheap magazines.
 

railroader

New member
You know it's odd that the 8 rounders don't work. I have 5 8 rounders for my P97 and I have had zero issues with them. Three of them were 7 rounders that I converted to 8 rounders. As for wilson followers I have used them also and they worked. Mark
 

madmag

New member
lee n. field said:
Not being able to use GI magazines probably cuts down on Ruger having to deal with support problems, with random cheap magazines.

That appears to be the thinking, and I can see their side. But I wish I had the option of dropping in one of my good 1911 Mec-Gar 8 (extended floor plate) round mags. I should also mention that when it comes to standard 1911 mags I have never had any luck with 7 round converted to 8 round mags. This is done by small changes in the spring and follower without extending the floor plate....never works well for me.

Anyway you can use 1911 GI mag internals (springs/follower) to re-build a P90 mag. But best to stick to skirted followers.
 

madmag

New member
Doug11606 said:
Both mags work flawlessly.

Yes, some 8 round mags do work. It is important to understand how you get a mag designed for 7 rounds (JMB's original design) to work with 8 rounds. The spring has to be changed in shape a diameter, and the follower has to be changed not to bottom out. In other words, there is just barely enough room for the 8th round. I am saying that this is on the edge for working. If it works fine, but just a little off and you will have problems.

8 round mags with an extended bottom plate for the extra round work just fine.

So, I don't doubt your 8 round mags work, but (my opinion) they are on the edge for getting 8 rounds into a space designed for 7 rounds.
 
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