Guy with 'Trouble Carbine'

[painter777]

Yesterday I had a friend stop by with a buddy of his towing along a Stan Pro carbine.
He had called and said they were having multiple problems with it and had been trouble shooting it for weeks. Sluggish was the word they's use over and over. Even before the gun was out of it's case they started with everything they'd checked, swapped, replaced, cleaned, oiled and greased. According to them I was their Hail Mary before the owner tried to find a gunsmith or just sell it. Once out of the case I thought of how much wiggle room there is between what 1 guy vs anothers idea of clean and lubed can vary. I'm a bit OCD when it comes to cleaned and lubed, but I was raised that way. This was a nice rebuild by Stan Pro with what looked to be a new frt sight added, a Type III bayo, adj rear sight and flip safety. It looked like the guys at Stan Pro rebuild were proud of it. "$500" said the owner..... "$500 will buy it if you think it's worth it to you." I could feel his frustration and seen my buddy roll his eyes at the same time. Told him I'm a buyer at $500 but if I were you I'd get it running right and if you really want to sell add 3 or 4 hundred more to that price.
All the while this 8+ on a scale of 10 Stan Pro stock warming the whole room.

Back to 'Sluggish'
Without a mag inserted I pulled back the slide and released it a few times. As I did so I could see the slide rails were lightly greased. Bolt was rotating and locking down neatly.... But something in the Sound. It didn't have that familiar Ker Chunk you hear. Ker Chunk... Ker Chunk.... I was looking it over as they were telling me about putting in a new GI Op spring and how the bolt was pulled apart lugs greased and cleaned. Gas piston and Cylinder rinsed with solvent. It got to where it was hard to concentrate on it because every time I started to mention something they'd tell me "We changed that or checked that." Finally I guess I barked a bit telling them.... "Then why did you bring it to me?"

I know they were just frustrated so we all took a breath. I loaded a mag of dummy rounds and hand cycled them with no problems. But it still felt slow when releasing the slide. "It's a new GI" they kept telling me, but it just didn't have that Snappy Ker Chunk sound. Best I can describe it was "It was Sluggish." I was ready to pull the action from the stock to have a look see when I noticed a pretty heavy finish wear pattern on the right rail forward of the slide stop pin. The finish was worn clear away from the Slide stop pin hole to full travel forward. I felt 'The Grin' coming on but didn't want them to see it. A prolong their misery move on my part. I pulled the slide back and pushed the pin down to the locked down position. It held firmly...... too firmly, I nearly had to bang it forward to pop up and even then I could see it wasn't completely retracting upward. This was causing a drag on the slide, sorta like driving with the parking brake partially on.

I pulled the action from the stock and pulled the Op Slide off. The inner pads and outer pad looked good with little signs of wear, all three having a light coat of grease.. same as the inside of the Slides/Bolt right lug connection. Spring was new like they'd claimed.
When looking in to the Slide stop pin it had a gritty feel to it. When pushed down it took some effort to get it to pop back up, but wasn't traveling all the way up. While taking it apart I found the Friction spring was mangled and also some hard crusty crud sorta welded to it. It was the late style stop pin. I robbed a spring from another slide, cleaned out the opening on his and put it back together. First try it snapped down then back up as it should.
Put it back together, locked it down and it easily released when drawn back. Now when hand cycling I could hear the crisp clear metallic Ker Chunk.. Ker Chunk !
Went ahead and hand cycled 3 or 4 mags through it with no issues. Slide stop pin showing just enough reveal as expected when in the up position. And holding as expected when in the Slide locked open position.

They called me this morning while leaving my buddies shooting range. 150 rounds without a issue. First time I've seen or heard of a Slide Stop pin causing an issue (other than not holding). So I doubt if this is a common problem..... just another little something to keep in mind if one of your babies is being finicky.

Me.. ? I'm just enjoying the day

Cheers All

[browningautorifle]

Good, an easy fix. That's why they think you're a high priest of the carbine...keep it that way. I've had a few come over in a firepail too...

[jimb16]

I've seen that problem once before. The guy removed the pin then crunched the spring reinstalling the pin. His own fault....

[Bruce McAskill]

Your the carbine guru on the forums. You did well and your friends will sing your praise forever. Good catch and diagnostic Charlie.

[DaveHH]

I've always marveled at the slide stop pin and the whole mechanism as well. What a simple cheap great working solution. They removed almost anything that you could do to make it fail. I suspect that most people have no clue about how it functions and because of that they butcher it when removing/replacing it. The little slope on the ramp and the one side loaded spring....wow. They even made it impossible to put the pin in backwards, anticipating fools handling it. If the pin wears and rounds a bit making the ramp become a hair trigger, you just turn the pin around to the unused side. Smart.

[frankderrico]

Charlie, The Carbine Meister!! Nice fix!!

[tenOC]

Charlie the Painter?! That guy owes me money.

[painter777]

Ten,
Thx a lot........ Here I was looking like a friendly go out of my way People person.

Did you already spend that $20K ?

Only guy I ever end up owing $$ to is Nigerian Bob.
You can't beat his interest rate of 0.00%.
But he has a way of pressuring you to get him paid off quickly by leaving your purchase out in the shed rusting

Other than him, my other funds get donated over the Craps table.......

Be there Baby !!

77.7 miles to my parking spot

[Mark Nevins]

Nice analysis and fix. Great work!

[tenOC]

Ten,
Thx a lot........ Here I was looking like a friendly go out of my way People person.

Did you already spend that $20K ?

Only guy I ever end up owing $$ to is Nigerian Bob.
You can't beat his interest rate of 0.00%.
But he has a way of pressuring you to get him paid off quickly by leaving your purchase out in the shed rusting

Other than him, my other funds get donated over the Craps table.......

Be there Baby !!

77.7 miles to my parking spot

I bet you have a lucky parking spot, but what if someone's in it already? Do you offer him $20 to move? Oh, I know..you order a tow truck saying 'your' car is stuck in a certain spot and need it towed.