Correcting the gap between cylinder and forcing cone on '51?

[illus1on]

Hi everybody!

Today my question is... how to correct the cylinder gap on an 1851 navy by ASP.

The gap on mine is far to big and im sure im losing a fair amount of velocity and muzzle energy due to it. i have concocted a few ideas but still have some questions..

My first idea was to file the area where the 2 pins connect to the barrel assembly thing, and then file the pins down a lil bit aswell incase the holes arent deep enough after fileing but then after i do that, even if the gap is exactly how i want it, im wondering if the big flat pin that holds everything together will still fit in properly with the changes i want to make??

I'm open to any suggestions you all may have.

-illus1on

[Hawg]

What are you calling far too big? .012 isn't unreasonably big. If you file down the barrel lug you throw the wedge slot out of position. You might be able to file the slot in the arbor to fit and weld the other end up.

[mykeal]

Hawg's right. The proper way to 'adjust' cylinder end gap is to work the end of the arbor (preferred) or the wedge slot.

[illus1on]

well the gap when pulled back at half cock is a few milimeters its pretty excessive, it def needs correction.

[illus1on]

and is there any way you guys mite be able to draw me a rough diagram in mspaint or somthing?? so i can understand a little bit better what your getting at??

I'd really like to fix this, but at the same time i dont want to do anything thats going to damage my weapon. It does fire and still has a good amount of velocity/muzzle energy but im positive the gap is far too big.

[mykeal]

Unfortunately, I don't have access to drawing tools to make the diagram you request.

If the cylinder end gap is truly too large (over 0.015"), that suggests that the cylinder arbor pin (the large round pin the cylinder fits on and rotates about) is bottoming out in it's cavity inside the barrel assembly block.

You really need to measure the cylinder end gap to be sure it's too large. And do it with the hammer down; measurement of end gap with the hammer at half cock is meaningless as there is no constraint on the cylinder motion.

To check the arbor pin length, remove the barrel assembly and the cylinder, then reinstall the barrel assembly upside down; that is, with the lug that fits over the two small pins up instead of down. Push it on as far as it will go, making sure the wedge doesn't interfere in the slot (you can actually remove the wedge from the barrel assembly for this test). Then rotate the barrel assembly around the arbor pin until the lug which fits over the two small pins is touching the pins. The back face of the lug should just match up with the front face of the frame where the two small pins are located. If it's too far back (towards the recoil shield) the arbor pin is too short (or the arbor pin hole is too deep). If doesn't reach the frame face the arbor pin is too long. Either add material using something like JB Weld, silver solder or weldment, or file to remove material.

[Hawg]

Sorta like this. If it doesn't match up flush it need adjustment.

[madcratebuilder]

http://www.theopenrange.net/articles...a_Part_One.pdf
http://www.theopenrange.net/articles...a_Part_Two.pdf

The barrel lug should just contact the frame or be .001 from the frame when the arbor is bottomed out in the barrel lug. If the gap is to wide at this point then the frame and arbor require modification, and possibly the wedge slot.

[jldee55]

This a brass frame or steel one..

[illus1on]

Hi guys.

i did what you asked and it is too far back (going past where it is supposed to)

what confuses me tho is if its already going too far back and if i add material to correct this wouldnt that make the gap even bigger?

ill try and obtain a caliper or some feelers to measure the gap.

and this is a steel frame.

[illus1on]

Hey guys i decided id try and take a picture of the gap (with hammer down and pulling back on the cylinder) to show you. my personal opinion was it was too large i could be wrong tho.

BTW sorry for the terrible picture. i used a little flip phone to take this pic

[Doc Hoy]

....in a similar situation...






BUT!

In order to get the union of the two parts to look right it takes either careful work by hand or it takes a milling machine.

AND!

As others have said, this may throw off the arbor length and the location of the slot.

I think that barrel did not come with that frame or perhaps that cylinder did not come with that frame and barrel.

[LeadZinger]

Doc has a good point. You may have mismatched components among frame, barrell and cylinder.

Post another photo showing the gun completely, views from both sides if possible. That might help indentify just what you've got.

Looking at the picture you posted it looks to me that the hammer is standing much to proud (high) of the cylinder and that it could possibly be a rebated cylinder. Personally, I have not seen a rebated cylinder on a '51 Colt Navy in 36 cal., but then again it just might be the picture quality.

I've been wrong more than right and my eyes are not what they used to be but my advice is don't do anything until you get proper indentification of the gun.

[illus1on]

hi guys, yeah its possible the cylinder is from a diff gun i know the frame and barrel match tho. and its not .36 its .44 i use .454 balls and #10 caps and goex FFFg

ill try for some better pictures im on my laptop now maybe i can use builtin webcam. also the cylinder has engraving on it if that helps. when i looked up all the makers marks on it i discoverd it was made in the 70's i forget which year exactly i think 76 and its produced by armi san paolo (euroarms)

thanks for all replies everyone esp those taking time to help which is all of you!

[illus1on]

Heres the best i can do for now, ill have to borrow a digi cam to get proper pictures. ive got pictures i took of it with a digi while it was all taken apart and being cleaned but i cant seem to find them right now, ill keep looking and post back if i find.

heres this for now though :

=========================:EDIT:=========================

Can i borrow your tools doc?? lol

---I JUST NOTICED THE PICTURE IN THIS POST IS MIRRORD, COULDNT FIGURE OUT WHY I WAS SEEING DIFF SIDES OF GTHE PIN IN THE DIFF PIX WHILE IT APEARD TO BE SAME SIDE---

thats what i get for using some cheap online snapshot program lol.

[Doc Hoy]

Looks like this might be a steel frame revolver. If that is the case it is worth a little extra effort to get it right. You could purchase a new cylinder for somewhere around fifty bucks and if that is the actual problem you would save yourself a lot of headaches. Do some homework before going that route.

If it is brass, I would not put a lot of money into it. You could part it out and make enough on it to buy yourself a good used but good condition revolver.

[illus1on]

yeah it is steel doc, i think ima try and get a new cylinder for it before i go screwn around with any of that.

if i had access to the tools you do tho i would have prolly done it already lol.

Thanks again for all the replies everyone!

-illus1on

[Noz]

I wouldn't sink too much money in an ASP gun. If you did all the work and got it right you still will have an ongoing problem with parts.

[illus1on]

Yeah its nothing for me to buy **** for it im not worried about money, im working on getting a restricted licence right now anyways so i can buy the weapons that truely interest me, thats not saying i dont love this type of firearm tho its got its own appeal forsure.

I would just like to have it working properly. even as it sits it fires almost every time and when it dont its usualy due to a faulty cap or the weapon getting too dirty.

Also at 50$ for a cylinder i dont see te big deal, i originaly planned to convert it to cartridges anyways so 50 seems like nothing compared to what a decent conversion cylinder and ejector and the necicary modifications would run.

[illus1on]

Out of curiosity tho what do you mean exactly by ongoing problems with parts? is there certin things that keep needing repairs on this paticular weapon?

[Doc Hoy]

....Original internal parts (by "original" I mean the original parts in some of the replica revolvers) were less than perfectly heat treated.

In fact some of the builders of kits from the seventies recommended that kit builders get smart about heat treating.

Parts for ASM and ASP are hard to get and so repairs and replacements are done with Pietta parts or Uberti Parts or other parts which are not specifically designed for the replica in question. They need to be fitted and most often this is done by filing on the replacement part and so even if the part was heat treated, that hardened metal may be removed during the fitting process.

So the problems are:

1) Properly fitting parts are not easy to find and many times you don't know until you get the parts.

2) Parts which don't fit need to be worked to get the pistol functioning properly.

3) The working of the parts MAY or MIGHT reduce their hardness and consequently their reliability in the application.

[halfslow]

Doc Hoy
Thanks for that picture of the mill for adjusting cylinder gap.
It solved my problem.

I recently picked up an almost new Dance by Pietta with about a .030 gap.
Last night, using my mini-mill, I whacked .025 off the front of the frame (the front surface looked like it was finished by scraping it on the concrete driveway).
Today when it warms up I need to take a few thou off the forcing cone to square it up and give me about 8 thou of gap.

Funny thing is the arbor and wedge fit is perfect now.

[Doc Hoy]

Try this trick for taking A TINY BIT off of the forcing cone.

Take the wedge out and turn the barrel on the arbor. You will likely need to hold the frame in a vise.



Sorry for using a junk pistol for these photos. But you get the idea.

Then put a thin file between the cylinder and the forcing cone. Put some sandpaper over the file. The purpose of the file is to give you a hard flat surface. (A file also does a good job of holding the sandpaper in one place.)



Then slowly work the barrel back and forth pressing down ever so lightly so as to remove metal from the forcing cone. Take the barrel off frequently and inspect the cone to make sure the process is doing what you want it to do.

[halfslow]

That looks like a great way to sneak up on the proper gap and leave a smooth finish.
Right now, the gap is 6 thou on the left and 4 on the right, and kinda crooked from top to bottom.
I figure the mill, using about 2 thou passes, will straighten it out.
Then I can use the wet-or-dry to leave a surface that will be easy to clean.

[Fingers McGee]

Excellent idea Doc. You gonna produce a picture series of rehabbing that brasser???