Springfield 1911 in 9mm

[Burnsome]

I've got a matched pair of stainless 1911's from SA.  The 45 functions fine, but the 9mm version almost always fails to hold the slide back on the last shot.  Got 5 SA 9mm mags and its the same no matter what ammo used or how well the gun is cleaned.  Any RKI's out there who might know what I need to check, or should i just send it back to SA for a checkup?

when checking with empty mags, the slide always stays back when manually checking.  when firing live rounds is when it failed to hold back...

[ronsunni]

Check out the 1911 forum for any problems with yor guns. :-)

http://www.1911forum.com/

[Mikey]

Hay Burnsome:  Your 9mms may not be hot enough to send the slide far enough to the rear to lock the slide back.  They might be hot enough to get the pistol to cycle but not enough to function properly.  

You did not mention what ammunition you were using.  I have a couple of suggestions though:  (1) use some heavier loads and see what happens  - by that I mean some 125 grain loads at 1150'/sec, or some cast handloads with 150 or 160 grain bullets or (2) use a slightly weaker recoil spring and your slide should stay locked back.

When I suggested heavier loads I was not referencing factory ammo, I was referring to handloads.    I just think you have to heavy a recoil spring.  This be Mikey and I hope this helps.

[Burnsome]

thanks for the tip mikey - good suggestion on trying different ammo.  i was thinking it was/is the magazine spring being too weak.  i've been using ga arms 115 and 147gr loads (factory reloads), but have some hotter factory winchester that i can try out and see if that is indeed the problem...

[Mikey]

burnsome:  I looked at your response but don't really think it is the magazine.  If you have been using reloads in those two bullet weights, the 115 and the 147, they just may not have enough poop to fully cycle that action.  in addition, you are using reloads which may be on the conservative side of having the proper poop.  

I would think that with the 115 grain load you might need somewhere around 1150 or better to get that heavy slide to cycle properly - with the 147s, they should be moving at close to 1,000 or better.  I don't know hwo came up with the idea that a 147 grain 9mm should cruise at less than 1000'/sec, unless it was some genius who thought they needed to be subsonic for clandestine or covert FBI ops but unles syour 9mm is tuned to that load she may not cycle the pistol properly.  

Your 9mm sits in a 45 and needs some healthy poop to get it working right.  You should be able to cure your problems with either some healthy reloads or hotter factory stuff, or a slightly weaker recoil spring which you  can get from Wolfe springs in PA.

Hope this helps.  Mikey.

[Bob_K]

If the slide fails to lock back, you might check to see if the magazine follower has over ridden the slide stop.  This can happen if the 9MM slide stop got switched for a .45 slide stop.  They look the same but are slightly different dimensions.  I tend to agree with the others, though, that it is probably the ammo without enough "oomph."