Belt Mountain Base Pin

[curioushooter]

So I got my Ruger Bisely New Model Blackhawk "Flat Top" 44 special yesterday. Pretty Sweet. Why didn't Ruger make this 60 years ago? I had a NM SBH Bisley with a 7.5: tube on it and never warmed to thing due it its ponderous size. This thing is Just Right IMO. I don't know about what others think on this matter but I think the newer Rugers (this one made 2012) is far nicer in the fit-n-finish department than older Rugers. It certainly rivals anything S&W has put out since about 2001.

Already got my Belt Mountain #5 pin. But here's the hitch. The Belt MTN will go into the frame hole just fine and it will go into the rear of the cylinder hole just fine, but it will not press through the front of the cylinder hole. It will go in about 90% of the way from the backside. I think there must be some bur or constriction in the cylinder hole that is doing this?

Kyle at BLT MTN said I can hone the pin or the cylinder. What do you guys think?

I also thought of electroplating some copper onto the surface of the factory pin to tighten it up. Anybody try that?

I was surprised at how good the trigger was. Certainly the best Ruger revolver trigger I've experienced...in fact I think it may have been worked on. The hammerspring is stock but it is clearly a reduced Wolffe trigger spring in there. Maybe the hammer or trigger was worked on?

I haven't undressed her yet (I know pathetic). Wanted to go over to my firend's house who has a set of pin gauges. See what the throats are and if there is the notorious barrel constriction.

[LUCKYDAWG13]

I would hone the pin

[megasupermagnum]

I too would do the pin, the easier of the two to replace. It wouldn't hurt to take a close look with a light at your cylinder to make sure there isn't a burr either, but being a used (likely fired) gun, it should be gone by now. I too think highly of the newer Rugers. I've got older ones too, but as far as I'm concerned, Ruger has been making the very best revolvers they have ever made right now. I would never buy a new S&W.

Enjoy.

[curioushooter]

The thing is used but I doubt it's been fired. Not a trace of residue anywhere, no blast marks on the front of the cylinder, barrel/chambers.

It's obvious to me that the cylinder hole has a taper . The only reason why the factory pin goes in is because it narrower than the belt mountain and therefore has slop. I do get the idea of it being easier to replace the pin than the cylinder, but the cylinder is the part that isn't quite "right." If any taper exists in the cylinder hole it should be narrow at the back and wide at the front---opposite of what is going on here.

Honing down the pin will only make it sloppier in the frame hole where it fits well presently, too.

[megasupermagnum]

Well if you you have reason to believe the cylinder is the problem, then it should do no harm to hone that out. A split dowel, with some emery cloth should lap it out. I just did a quick check on a 357 magnum blackhawk. That cylinder center will fully pass a .251" pin gauge, but will only start a .252" gauge in the front, not at the back. Assuming the same dimeter, it wouldn't hurt to turn a 1/4" drill by hand through it to see if there is any burr. If not, go slow with the emery cloth, and it should smooth out fine. That might be half the battle, is just a rough finish in the hole.

[curioushooter]

So I am happy with what happened here.

After cleaning with solvent, I put a wee bit of 15 micron microabrasive film with a PSA (adhesive backing) on then end of a chopstick and put it in front of the cylinder hole where there was a constriction. Spun the cylinder around the chopstick which was clamped in a vise (only the weight of the cylinder bearing down) until the belt mountain pin would just go in. Then I took out some JB compound and swabbed the entire cylinder hole and the belt mountain pin and rubbed it evenly. Then I removed the JB. Put a little light oil on and pushed the pin in and slid it around and whatnot. Then assembled it in the revolver and it's very tight now. Works just as well as with the sloppier factory pin and I think I eliminate most if not all the taper that existed (the front of the cylinder hole would not take a .250 pin gauge while it would take it from the rear). I think this was due to some rough finish, perhaps some chips got dragged. Who knows. It's fine now. Was very little effort to correct.

The belt mountain pin a great upgrade IMO. Makes it tighter and is more secure and easier to remove.

After pin gauging the whole revolver I have to give a solid A- if not A to Ruger. All six throats measure +.431 to -.432 via pin gauge. The barrel constriction is barely detectable. A .416 pin will run through the barrel from muzzle to window but a .417 is NO GO. Talk about deep grooves. I didn't slug it but I am assuming .429 or so and that means 6 to 6.5 thousands deep on the side! B/C gap just over 4 thou, won't take a 5 on any chamber.

This thing should make for an EXCELLENT cast boolit launching device.

My only quibble is the trigger which does have some creep. It is not gritty or even that inconsistent but it is there. It seems of so little consequence that I am debating if I should do anything about it. My understanding is of Blackhawk Hammers (Bisleys are stainless it appears) are through-hardened, so one is sort of at liberty to judiciously remove material from the hammer to shorten the tigger sear engagement surface. It does have a trigger better than my G2 Contender that has been worked over by E A Brown. Still not as good as a trigger as any my S&Ws, though.

Probably going to rip it apart tomorrow and maybe polish it a little. We'll see. But if you have any doubts about these I say go for it!

[Rodfac]

Have you shot it yet? Before I'd change anything on a new to me, handgun, I'd shoot it after a good cleaning. I've got three of the Flat Tops in .44 Special and all of them will hold less than 2" groups at 25+ yds with Skelton's classic load. Two friends have a couple as well, and both are superb shooters. Triggers are ~4 lbs....about where I like them for carry. YMMv Rod

[Lloyd Smale]

belt mountain pins used to come needed to be fitted because rugers were sure not the same and the more precisely its fit the tighter your gun will be. I think it was later on the kelly started selling the one size fits all pin.

[fourarmed]

I put a Belt Mountain in my .45 Colt Bisley, and eventually went back to the factory pin. I thought it shot marginally better with the factory pin. Don't know why that would be, unless a little slop let the bullets center up in the barrel better.

[DHDeal]

I put a Belt Mountain in my .45 Colt Bisley, and eventually went back to the factory pin. I thought it shot marginally better with the factory pin. Don't know why that would be, unless a little slop let the bullets center up in the barrel better.

That could be it.

I've not had that issue and every RBH I own has a Belt Mountain pin. I prefer a tight gun but sometimes with all of the tolerance stacking on a particular revolver, it might need the little extra that the larger pin removes.

[daleraby]

Y'know, I never thought of using a chop stick for a gunsmithing tool... and I got a bunch of 'em in a container on the counter in plain sight. My own Ruger/Lipsey .44 Special did not really NEED a No. 5 Belt Mountain base pin, but I liked the looks of the pin on Elmer's Colt No. 5, so I ordered one up. It fit with no issues and did not walk out even under my heavy "shaking hands with God loads".... which is a Montana Bullets 255 grain "Keith" bullet atop 15.5 grains of 2400. A nice side effect is that this pin will not roll off the table when I am cleaning the gun!

[contender1]

An update to this thread about Belt Mountain.

Apparently Keyle is planning to retire. And he is not making any more pins. He's looking for someone to take over the business,, but as of a week ago,, no takers. He has very few pins left & then he's done.

Sad to see a top quality product disappear.

[Thumbcocker]

So I am happy with what happened here.

After cleaning with solvent, I put a wee bit of 15 micron microabrasive film with a PSA (adhesive backing) on then end of a chopstick and put it in front of the cylinder hole where there was a constriction. Spun the cylinder around the chopstick which was clamped in a vise (only the weight of the cylinder bearing down) until the belt mountain pin would just go in. Then I took out some JB compound and swabbed the entire cylinder hole and the belt mountain pin and rubbed it evenly. Then I removed the JB. Put a little light oil on and pushed the pin in and slid it around and whatnot. Then assembled it in the revolver and it's very tight now. Works just as well as with the sloppier factory pin and I think I eliminate most if not all the taper that existed (the front of the cylinder hole would not take a .250 pin gauge while it would take it from the rear). I think this was due to some rough finish, perhaps some chips got dragged. Who knows. It's fine now. Was very little effort to correct.

The belt mountain pin a great upgrade IMO. Makes it tighter and is more secure and easier to remove.

After pin gauging the whole revolver I have to give a solid A- if not A to Ruger. All six throats measure +.431 to -.432 via pin gauge. The barrel constriction is barely detectable. A .416 pin will run through the barrel from muzzle to window but a .417 is NO GO. Talk about deep grooves. I didn't slug it but I am assuming .429 or so and that means 6 to 6.5 thousands deep on the side! B/C gap just over 4 thou, won't take a 5 on any chamber.

This thing should make for an EXCELLENT cast boolit launching device.

My only quibble is the trigger which does have some creep. It is not gritty or even that inconsistent but it is there. It seems of so little consequence that I am debating if I should do anything about it. My understanding is of Blackhawk Hammers (Bisleys are stainless it appears) are through-hardened, so one is sort of at liberty to judiciously remove material from the hammer to shorten the tigger sear engagement surface. It does have a trigger better than my G2 Contender that has been worked over by E A Brown. Still not as good as a trigger as any my S&Ws, though.

Probably going to rip it apart tomorrow and maybe polish it a little. We'll see. But if you have any doubts about these I say go for it!

My standard procedure on new model Rugers is to disassemble and polish all the internal parts that rub on each other with a dremel tool and a buffing wheel. Use metal polish. Then install a 20oz trigger return spring. Lastly dry fire, dry fire, dry fire. The result is a nice trigger without having to worry about hard primers not popping.