Slide stop locks slide back on 2nd round

[spider445]

After putting my Para back together with a new barrel and #3 barrel link, took it out to the range and fired several magazines. On three of the 4 magazines containing seven rounds of ball the slide lock would lock the slide back after firing the second round. This didn't happen prior to the new barrel being installed. Also the gun wouldn't go into battery with the last round several times.

Took it apart and changed out the barrel link to a #5, seems that the ramped barrel doesn't move back as much on the frame as the #3 link did, then filed some metal off the side edge of the slide stop, back to the range in the morning.

Gun cycles fine by hand, anybody have ideas as to why the slide stop is locking back after the second round is fired?

Thanks

[John]

I can't understand how the barrel link can affect your slide stop.

Does your problem occurs only with the second round or with other rounds in the magazine as well? What ammo are you shooting?

[spider445]

Locks back after the 2nd round is fired, using 230 grain ball ammo.

[John]

How old are your magazines? What magazines are they? First two round firing fine, then it jams, then it cycles fine again. Something is weird here.

One more thing. Remove the slide stop from the slide but leave the outside part of it hanging down into the trigger guard. Leave the pin inserted into the frame and through the barrel's link. Press the slide back from the muzzle until it stops. Can you turn the slide stop freely or is it tight?

[1911Tuner]

Why did you install a #5 link?

[spider445]

Gun doesn't jam after firing first two rounds, the slide lock engages the slot on the slide and locks it back. Upon dropping the slide it's fine for the rest of the magazine. I have a 5 barrel link set just trying different things. With the #5 link in the barrel doesn't move backward on the frame as much as the #3 link.

[1911Tuner]

Gun doesn't jam after firing first two rounds, the slide lock engages the slot on the slide and locks it back. Upon dropping the slide it's fine for the rest of the magazine. I have a 5 barrel link set just trying different things. With the #5 link in the barrel doesn't move backward on the frame as much as the #3 link.

Spider...Have you run a barrel timing test with the new link?
Longer links delay unlock and linkdown timing. That can do some serious damage to the barrel and slide if it's not the right length.

[spider445]

Johnny, can you describe how to do this test? I did notice a slight scrape on the top of the barrel hood when I changed the # 3 link to the #5 link. Thanks Greg

[1911Tuner]

Spider,

The scrape may not be signifigant. Check first to see if the barrel is standing off the frame bed by more than the thickness of a piece of crepe paper.

Install the barrel in the frame...slide off. Slip the slidestop pin through the link, and push the barrel fully down and back. The long link may be holding the barrel off the bed in compression.

While you're doing the check, consider that the barrel's rearward movement should be stopped by the frame's vertical impact surface...and it should do it
before the lower part of the rear of the barrel hits the bed. When it hits the impact surface, there should be .010-.012 inch of clearance between the
underside of the slide and the top of the barrel when the slide has moved .250 inch. It can occur a little earlier...but not later..or at least no later than .260 inch of travel..and even that's pushing it.

Check the top fornt corners of your barrel lugs to see if there's a sign of rounding or other deformation. They should be clean and square.

[spider445]

Johnny, I have a ramped barrel and the lug configuration is different than a standard 1911 barrel. The ramp rest on the slot cut in the frame regardless of which link I use. The area that extends down into the frame at the rear of the barrel ramp is .240, the measurement from the slot cut in the frame which the ramp rides on to the base is .270. With the #5 link in the gun I could load five 7 round magazines and cycle them by hand or by using the slide stop without any problems. Barrel lock-up was tight. Using the number 3 link when I used the slide stop on a fully loaded magazine it would fail to go into battery, with the round entering the chamber 3/4 of the way and the rear of the case getting stuck between the extractor and breach face. I would remove the magazine replace the round and cycle it by hand not using the slide stop and it worked fine. This happened on two out of five magazines.

[1911Tuner]

Tryin' to get my head wrapped around the issues here, Spider.

I don't mess with the full-ramped setups very much, so I'm not too familiar with'em...and don't much care for'em. The angles are all wrong, IMO. There are a few things that are sure, though.

The link shouldn't reposition the barrel horizontally in the frame. Tighter lockup with a longer link suggests that the barrel is locking on the link...which it shouldn't do. The barrel's rearward movement during the cycle still has to be stopped by a vertical surface and not the link.

Sounds like either your frame was badly machined or the barrel itself is out of spec. I'd suggest a smith who is well-versed in the 1911, and particularly the ones with fully-ramped barrel arrangements.

[spider445]

Good News, went to the range this morning and test fired the beast after replacing the #3 link with a #5 link, and beveled back the area above the slide stop flat that engages the magazine. Seven magazines of 230 grain ball with no problems. Hopefully the problems are solved. Thanks to everyone for their help, Spider

[steph]

One more thing. Remove the slide stop from the slide but leave the outside part of it hanging down into the trigger guard. Leave the pin inserted into the frame and through the barrel's link. Press the slide back from the muzzle until it stops. Can you turn the slide stop freely or is it tight?

I tested a new norinco this way and the slide stop will turn but a little tight. The bottom of the rear of the barrel is resting on the base of the frame. Is this common in new guns?

Thanks
Steph

[John]

This probably means that your barrel is NOT stopped by the vertical surface of the frame, but by your link. As for solutions, since this is a rather complicated issue (at least for me, at 07:30 am), I 'll let someone else suggest ways to eliminate the problem.