Author Topic: Switching NMSBH Cylinders ???????? (Read 1210 times)

J.Solo · « **on:** February 15, 2003, 07:15:13 PM »

I have two New Model Super Black Hawk .44 magnums. One has a 10.5"barrel and the other HAD a 10.5" barrel that I had cut to 5 5/8" then MagnaPorted. The 5 5/8" model is my favorite.

The cylinder from the 10.5" gun is slightly longer and fits tighter in the 5 5/8" gun giving me less cylinder gap. My question is: Is it OK to switch cylinders between the two guns?

Right now I have a .004" shim washer between the rear of the cylinder in the 5 5/8" gun in order to push the cylinder forward in order to decrease cylinder gap and remove some slight movement between cylinder and barrel.

The 10.5" guns cylinder fits tighter, without any forward movement and without the .004" shim washer when placed in the 5 5/8" gun.

I do notice some slight rubbing on the front of the 10.5" guns cylinder and the 5 5/8" guns barrel.

Is this making any sense? And can I make the switch?
My objective is to decrease the cylinder barrel gap to improve accuracy.
Thanks - J.Solo

KN · « **Reply #1 on:** February 15, 2003, 09:09:38 PM »

You have to have a minimal amount of play between the cylinder and barrel. If its too tight the powder residue will cause the cylinder to start binding up. If its rubbing, its too tight. You should be seeing excessive gap with the other setup if thats what your wanting to do to the other gun. Too much gap and you have a fire ball around the cylinder between the barrel and cylinder. If you had two guns that measured the same you could probably do this, but I wouldn't recomend it in this case. KN

Hud · « **Reply #2 on:** February 16, 2003, 06:08:09 AM »

I have always thought that the forcing cone angle has a lot more to do with accuracy than the cylinder gap. Also if you are using lead bullets with tight cylinder gap, the lead and powder can clog up the gap and stop the cylinder from turning. You don't want this to happen when that big buck is in your sights. :eek:

Hud

Bullseye · « **Reply #3 on:** February 16, 2003, 04:46:23 PM »

You asked if it was okay to switch cylinders between the guns. NO, NO and NO. I think the cylinder in a revolver has to be timed with the individual frame and you cannot just switch the cylinders betweens guns.

KN · « **Reply #4 on:** February 16, 2003, 05:41:31 PM »

I'm no expert on this but I believe if you have a timing problem with a gun its a problem with the frame works assembly, and not the cylinder itself. Like I said, I'm no expert on this so some one please correct me if I'm wrong. KN

MS Hitman · « **Reply #5 on:** February 17, 2003, 02:12:45 AM »

Yes, go ahead and swap cylinders to see if the accuracy is improved or not. Ruger does not go to any great lengths ot fit cyliners to frames during manufacturing. I would not do this on a custom or FA revolver, but on the Rugers go ahead.

44 Man · « **Reply #6 on:** February 17, 2003, 01:10:10 PM »

If that cylinder gap really bothers you, (And shimming the rear of the cylinder is NOT the correct solution for this problem, trust me!) send the gun back to Ken Kelly at Mag-na-port, and ask him to set the barrel back to tighten the cylinder gap. Something any good smith should be able to do, but Ken is one of the best! BUT, other than pleasing you, (which is a major consideration) I'll bet you find that it does not affect the accuracy or increase velocity. One of my favorite Rugers has a huge gap of about .010, but still gets the highest velocity from my loads compared to other guns with about the same bbl length. Who can figure?

Flint · « **Reply #7 on:** February 18, 2003, 06:55:13 AM »

As 44man said, shimming the cylinder forward will not be advisable, it will increase the distance between the hand and ratchet and change the cylinder rotation, making a possible shortstroke and chamber misalignment with the barrel. What is the gap to start with? it shouldn't be less than .003, and is acceptable to .008 or if it all works, .01. If you shoot lead bullets, it's probably best about .006.

J.Solo · « **Reply #8 on:** February 18, 2003, 05:55:22 PM »

Thanks for the information guys. But it's not an issue any more. I traded the 10.5" NMSBK for a new in box, Ruger Old Army Stainless with adjustable sights, extra cylinder and Ruger presentation Walnut grips.

I have had a very thin shim behind the cylinder of the 5 5/8" Ruger NMSBH for many years now and have not noticed any short stroke or timing problems. I will give an exact measurement of the shim and the barrel gap with and without the shim as soon as I can measure it again. It's been many years since I installed the shim and I don't remember the measurements right now.

A close look at the forcing cone does show very little taper in the upper 1/4 of the barrel cone while the rest of the 3/4" on the cone looks properly tapered. Is there any recomended degree of taper for the forcing cone of a .44 magnum and should I have it re-cut so it's even all the way around. The cylinder does come closer to the bottom of the barrel than at the top thus giving an uneven cylinder gap. More gap at the top and less at the bottom. Any ideas on this???? thanks - J.Solo

KN · « **Reply #9 on:** February 18, 2003, 08:17:03 PM »

Either the end of your barrel is not square or it's not threaded into the frame square. Or the end of your cylinder isnt flat.or the axis the cylinder rotates on is tilted upward. Those would be the only causes I can think of that would account for that. KN