Barrel fitting question

Bottom line up front: where can I get a 1911  slide release that has a pin diameter of .196”? 

Watching my smith build my BE 1911 in 45 acp today. Using a Caspian frame/slide & Kart barrel. He cuts the feet at the bottom of the barrel so they will mate up with the slide stop pin. Tells me I need a slide stop with a .196” pin diameter but mine is an EGW size .200. The EGW sizes available are only .200” or .203”. Looking for suggestions where I can get a .196” slide stop. 

****CORRECTION**** the .200 slide release pin does fit in the receiver. I was incorrect when I said it didn’t fit the Caspian receiver hole. 

Thanks,
-Trevor

Take it to a machine job shop and ask them to machine it down to the dimension you want.  It will cost a few $ but you’ll get what you want.  Take the frame with you and explain that you want it to fit that.  They may suggest that you allow them to ream the hole to allow the existing pin to work as it is.  And then you’d have to adjust the fit of the barrel to the larger pin.  I’m not sure which is the best way, but there’s two ways to skin that cat.

Why would the gunsmith use .196" slide stop pin? Does this guy know anything about building a BE pistol? To take a .200" pin and cut it to .196" correctly in not easy! Yeah you can use emery cloth, Aluminum Oxide sand paper or abrasive stone but it will not be round or uniform. A Jig Grinder or Tool Grinder will do the job but it will not be cheap!

Find a used springfield slide stop typically 195-196

Smith probably cut the lower lugs with the 195 brownells cutter and doesn't want to fit it further. I would worry about upper lug contact/depth

The other question would be why a .200" pin won't fit a Caspian receiver.

The holes in the receiver can have burred up edges from the machining order that need to be cleaned up so check that.

jglenn21 wrote:Find a used springfield slide stop typically 195-196

Smith probably cut the lower lugs with the 195 brownells cutter and doesn't want to fit it further. I would worry about upper lug contact/depth

Yes, he used the Brownells cutter and suggested the use of a .196 pin. Now I am trying to find out who sells them at that size. 

Is the standard Springfield 1911 pin size in the 195-196 range? 

-Trevor

Too many variables……
If you have any vertical play in the frame to slide fit, the lug cutter will remove more than the cutter diameter because of gravity the slide will drop low. You have to cut your lugs and then use a pin gauge to see what your reality is for the slide stop pin diameter. This is a simplified explanation, there’s a heck of a lot more going on to fit a barrel correctly.
Jon

Yes the Springer pins are in that range, but

I have built quite a few 1911 .45acp pistols using Caspian frames. I've never needed a stop pin smaller than .200" I have a few that are not complete, hammer and sear pin holes are not done nor is the rail cut. I got them so I can Jig Bore the pin holes perfectly perpendicular, parallel and straight. I will grind the rails. But the slide stop pin hole is completed and to correct size. I find it odd that a Gunsmith will tell you the parts that are needed. Seems to me he don't know what he's doing! Probably trying to assemble a gun from supplied parts. Lug cutting the lug and finds that only pin size that will fit is .196", maybe by using a #9 drill though the hole in the frame is .201" the slide will close. I will never use a lug cutter!! That guy is not a BE gunsmith, later you will be back with other problems if you do find a .196" stop pin!

DA/SA wrote:The other question would be why a .200" pin won't fit a Caspian receiver.

The holes in the receiver can have burred up edges from the machining order that need to be cleaned up so check that.

****CORRECTION**** the .200 slide release pin does fit in the receiver. I was incorrect when I said it didn’t fit the Caspian receiver hole.

Well, I suppose since I verified the .200 pin diameter does fit in the receiver hole we can just file away incrementally at the lugs until a .200 provides the appropriate lockup.

The smith was suggesting using a .196” to start with because over time the barrel lug/pin area can wear/loosen up. If I start with a .196” then I have the ability to move up to a .200 diameter pin a few years down the road if the lug/pin area has wear developing and needs to be tightened. That was the motivation behind his recommendation, to provide options and longevity in the barrel lugs. 

I suppose I could also file a flat on top of the .200 pin and do the same thing, yes? This would allow minimal removal of material from the barrel lug. Any pros/cons that you can think of relating to using a flat on top of the .200 pin instead?

I checked mine, it's .197 to .198, tapered and a bit out of round. MIM part, flash at the parting line is a little bigger.

The smaller pin might wind up beating the hole in the frame out of round?

As for turning one down ... I'd say no and if they asked why I'd tell them because there's no way they'd be willing to pay what it would cost. How would you hold it? Pot it in Cerrosafe, maybe. Froneck's suggestion of a Jig Grinder would be better than a Lathe, but still a fixturing problem.

Maybe with an external hone. But you still have to drive it somehow.

After some thought, it appears the EGW pin options are .200 and .203. This suggests that 1911 builders are using the .200 to initially fit the lugs to the pin. Over time as the pin/barrel lug relationship wears out the .200 is replaced by a .203 pin, the pin hole in the receiver is re-drilled to open it up to accommodate the .203, and the barrel lug is filed on to remove .001 or so as needed to accommodate the new .203 pin.

Is this how folks are using the .200 & .203 pin options?

Thanks,
-Trevor

There is more involved than changing pin diameters. EGW does have .206" though no .204 or .205", at least they did have a .206" because I have a few from them. There is more than lug wear. The link pulls the pin up and the lug pushes the pin down so after time the hole will wear oval. Also one has to understand a .2000" pin will not fit a .2000 Hole, it will have to be pressed in  therefore the slide being locked back by the magazine spring will not happen! Usually the hole in the frame is .201", now putting in a .196" pin will allow the pin to be pulled up and down creating impact and increasing wear kinda the difference between a push and a punch. I addition the upward force on the barrel is dependent on the angle at which the pin contacts the lug, lower the angle the higher the upward force prior to the upper lug alignment, changing that relationship can cause the slide to stop and not close. It's noticeable by the so called "bump" just before the lugs align but as the angle decreases the "bump" happens sooner until slide will not close. Properly done there is no "bump" and slide closes with smooth forward movement. So there is more involved in making a good BE gun that most typical gunsmiths don't understand. A BE gun must be able to group 2.00" at 50 yards and function reliably. Anything less will cause frustration and shooter will never rise in classification! I have seen some really good looking 1911s, a great show piece that will not be good enough for a BE match!!! Putting a flat on the pin will help, but again it will depend on how the flat is done and how the lower lug is cut. The flat will allow you to use a .200" pin but other problems will become evident.

In the mid-80s, the USMC armorers built 1911 pistols on a "cut pin."
The pin was filed by hand in a fixture that permitted filing the middle of the top of the pin. The ends of the pin were full diameter, but the middle of the top (where it contacts the barrel lugs) was filed to .196 or whatever size was needed to fit the lugs. The pin was rotated manually to create a radius on the filed portion.
The concept was that a new pin could be fitted easily to the pistol if the lockup loosened.
I watched the process several times from the back of the truck.

KC,

Shop made tool?

That is exactly how S&W fitted the barrels on M-52’s. The slide stops have obvious flats filed into them, no filing I can see on the barrel feet.

I am as impressed by the clean letter stamp on a round face as I am by the tool itself.

For KC. Another question

Was the cut pin a good concept? It looks good on paper.

And, were you a 2112?

That 1918 colt frame I have has a lot of slop in the frame cross holes, just ordered a EGW .200 should slip right in,  If you need a .196 I have one.

Jerry Keiffer fitted a new barrel to my hard ball gun and he machined a flat on the slide lock/release pin too facilitate lock up. I watched him cut the slot/flat on his milling machine.

chiz1180 wrote:KC,

Shop made tool?

Yes part of the list of tools I had to make in the machine shop before I moved out on the floor to start my OJT.

randy86314 wrote:For KC. Another question

Was the cut pin a good concept? It looks good on paper.

And, were you a 2112?

It's a very good idea. As a gun wears I can cut a new pin to get lock up back. That's the way we used to do it back in the day. Yes I am a 12.