Para 16-40 beats up guide rod plugs

[djcsmith]

My 1911 Para 16-40 has a bull-barrel and reverse full-length guide rod plug.

It keeps beating up guide rod plugs.

It starts with peening the lip of the plug, progresses to the point where the tunnel goes out of round, and binds with the recoil spring.

Left long enough, the plug splits along it's length. I am on my 4th plug.

I had the slide mating-surface milled square, as the peening always happens on the same side, but it keeps re-occurring.

I have also tried filing the mating surfaces of the slide to remove rough edges.

I'm not sure it is due to sloppy assembly after field-stripping, or the plug twists as the gun cycles.

See attached photos.

Any one else seen this?

David

[djcsmith]

I'm replying to my own post here. . . . .

I just had a thought; a year or two ago, I changed from running 14 pound recoil spring, to a 12 pound.

My issues with the plug may have started about this time.

If the plug is shifting during slide-cycling, this might explain it if one believes that a light spring may allow some "bounce" of the plug every stroke of the slide.

I am going to replace the plug with a new one, and at the same time try going back to a 14 pound recoil spring.

Still interested to hear if anyone has had similar experiences, as well as some theories for the cause.

[jcc7x7]

My first thought was to light of spring but you answered your own question.

I ran 13 lbs springs in a Para 16-40 for a long time with no ill effects, the slide was lightened some 4 cuts in the front of the slide, don't remember the weight

I don't remember mone having a collared reverse plug, did you have the slide milled out for that collared plug? If not that may be part of the reason its getting beat up thou I wouldn't think that the collar width would cause that kind of problems as long as it sits square against the dust cover.

Hmmmm?

[djcsmith]

Thanks jcc7x7.

Attached are a few more photos to help explain how the plug fits into the pistol.

I'm not sure what parts the Para came with originally, as I am the second owner.

It is one of the original Canadian made Paras.

When I first acquired it, it had some feeding issues, which were due to bad mags, since then has been a solid pistol.

It is a workhorse; with 10's of thousands of rounds through it, and runs reliably with most competition loads.

I have a match Tuesday, so I can test out my theory about the weight of the recoil spring.

Maybe a 14 pound spring will hold the plug from dancing about as the gun cycles.

[bountyhunter]

At the risk of heresy: I might try trimming a 1911 shok buff to fit and see if that stops the hammering from happening.

The other possibility would be one of those dual spring recoil assemblies if they make one to fit that gun.

I'd be interested to know if that came from Para because it looks nothing like my 16-40....

Edited March 21, 2016 by bountyhunter

[Aircooled6racer]

Hello: Are you sure that the springs you are using are 12lb? I use a 14lb for major and a 12.5lb for minor. I am also thinking maybe the spring is going into coil bind and causing that bulge out the side of the reverse plug from the spring pushing out there? Thanks, Eric

Edited March 21, 2016 by Aircooled6racer

[EclipseDS]

Somebody fitted a flanged plug. My 16-40 looks nothing like that and my plug goes all the way into the channel wiht nothing visible except from the front. You can see the rough cut. Maybe you/they tried a Briley plug? The more you use a lighter spring, the more it will bang and smash against the frame. The worse part is that the two small tabs left from cutting the plug channel would damage any shock buffer you might be trying.

I'm willing to bet that plug you're using now is loose fitting. Use a flange-less plug or trim those tabs. Flange should rest on the slide rails anyway.

[djcsmith]

Trying the 14 pound recoil spring tonight, with a new plug.

After the match, I'll strip it, and check for damage.

[kimberacp]

that plug should work, if your using the correct spring weight. 14 to 13 lb range should do fine. typically, bull barrel guns use a recoil plug with a step or in your case, the tabs. the back of the slide tunnel needs to be bored to accept the recoil plug with the step. the step or tabs is what keeps the recoil plug from rocketing forward, as opposed to a barrel bushing which locks in place into the groove inside the front of the slide

there is no need for shock buffs, just use the correct weight spring to avoid banging the slide against the tabs.

the recoil plug with the step is a much option. since you have a fitted bull barrel, I would go with that setup, a stepped recoil plug. yes, there will be a slight gap, since the rear of your slide was reduced to make clearance for the tabs.

good luck

[EclipseDS]

The step or the shoulder of the plug should be snug when inside the channel. I think it's pretty loose, that's why it's being beat up, because the plug rotates every time the slide moves. If you can't keep it in place, the tabs will be chewed up

[djcsmith]

Thanks for everyone's comments.

I looks like the heavier spring is the key to solving this issue.

Last night I installed a new Wilson reverse plug, and a new 14 pound spring.

My club-match last night was about 100 rounds.

So far, no peening of the tabs on the plug.

It seems that the heavier spring is doing a better job of holding the plug in place, preventing it from bouncing around.

This Sunday, I have a 7-stage match.

After that, I should definitely see if the heavier spring solves the problem.

If not, I'm about ready to revert to a bushing barrel.

BTW, I'm running one of the original Canadian-made Paras, probably built in the late 80's.

It has had 10's of thousands of rounds through it.

[djcsmith]

EclipseDS mentioned a Briley Plug. . . . . . . <Maybe you/they tried a Briley plug?>

I did a You Tube search, and found this video:

The poster of the You Tube video mentioned the reason he fitted the Briley Plug, was to prevent the rotation and damage to the reverse plug.

BTW, a Briley Plug has extra lobes which fit into the slide to prevent it from rotating. It requires some machining of the slide to fit the plug.

So my issue has been seen before.

In this case, rather than find the reason for the damage, he just prevented it from happening again.

If my situation continues, I have 2 solutions:

1/ Buy and fit a Briley Tube,

2/ Go back to a bushing barrel.

As the barrel in my pistol has seen so much use, a new bushing barrel might improve accuracy, and avoid the issue.

Sunday's match will determine if this is necessary.

I'll report back then.

[EclipseDS]

You can also try a reverse plug without a flange: http://www.shootersconnectionstore.com/Assets/ProductImages/S22R5C.jpg

The issue though is that your plug channel is chopped and this could damage the frame if the slide bangs against it due to the remaining materials, so maybe, Briley plug is your best bet.

If you cleanup the slide, you'll have more, cheaper, options.

[Yeti]

If you have room run an aluminum buff. Best fix is a properly fit supported hat style reverse plug eventually, though.

[djcsmith]

Thanks to all those who submitted suggestions on this thread.

I'm back from my match.

Between last Tuesday & today, I've put 250 rounds through the pistol, with a new 14 Lb spring & new reverse-plug.

The plug remains undamaged, so recoil spring weight is critical in this pistol.

I can't use a 12 Lb, without damaging the plug.

If this rears it's head again, I'll change to a different style of reverse-plug, as suggested by others; either a hat-style or Briley. (photos attached)

Both these options would require machining the slide to fit, but certainly better than a new pistol.

David

[kimberacp]

whether you change the plug or not, you have an indicator that using a 12pb spring is beating up your pistol. maybe you can us a 13lbs but anything lower with the barrel setup now, a 12lb would probably be right at the limit of what you can use.

Try a 13lb and see what happens? A 13lbs should be good enough for your gun.

[djcsmith]

I might try the 13 Lb spring, once all this has settled down a bit, and I learn to trust the pistol again, and get a back-up plug.

Last summer, I had to do a last minute switch to Single Stack with my .45, because my Limited Para had the reverse-plug flu.

[BSComp]

David,

It appears that your slide is not cut correctly. In the picture below, the area in the RED circle doesn't appear to be cut the same as the area in the BLUE circle.

The extra material that appears to be there in the RED circle coincides with the location of the "denting" or "marking" on your plug.

[djcsmith]

The two sides of the slide look different, mostly I believe, from having beat up several guiderod spring plugs.

It is easy to replace a plug, a lot more expensive to replace the slide.

The slide has been getting filed a bit whenever it gets too deformed.

I have been test fitting each new plug, and they do sit flat when new.

I'll be putting another 100 rounds through it tonight, and will examine the parts again after.

[Yeti]

Hi David,

Are you still running a 14# spring with no further damage?

Or did you end up fitting a supported plug?