Factory tolerances for the barrel/cylinder gap dims are .004-.008.



I would not close the tolerances much tighter than .004. The trade off for higher velocity is reduced reliability. Fouling on the front of the cylinder and back of the barrel can cause a cylinder bind. Lead bullets make this happen much quicker than jacketed bullets, obviously.



You might want to check the dimension of the cylinder throat. If those dims are too tight, pressures would be elevated.

Scrollcutter, they didn't say what the cylinder throat tolerances were, and I didn't ask. I told them the cylinder gap before they told me what their tolerance was.

I did measure the throats with a regular set of hand calipers, and I know they're not perfect but I think they're close enough to tell me that none of the throats are bigger than .499, I guess I could be wrong though. I don't shoot the gun more than every couple of weeks so I'm not sweating sending it in to them. Maybe they can tighten it up a bit. We'll see.

On a side note I understand that tight cylinder throats might make the pressure go up, however my velocities are way under what everyone else appears to be getting so I don't think that's the problem. I think the problem is lack of pressure.

I tried Lil'Gun a while back in several claibers and was disappointed in the lack of velocity I was getting; no where near what the loading books said. This was over a range from the .32 Mag to the .454 Casull.

Have you tried any other powders such as WW296 or H-110 and experienced lower velocities?

MSHitman, H-110 was going to be my next attempt but rather than spend another $20 on a pound of pounder that might not get me the results I want I figured I might go ahead and let S&W have a look at it first. I wouldn't be so pessimistic if I hadn't already tried two powders and they were both too slow.

I went to the range today with my 500 S&W with a scope on it that needed to be sighted in. I was shooting 400gr bullets that had a flat point so I made them into HP by drilling a hole in then. and once sighted in at 50 yds I shot a 5/8" three shot group with it.

The SW 500 is accurate,wait till you shoot at 100-200 yds you will be happy then also.
Sean

Kingfisher,
I get 1912 with my 350 Serria's using LIL-GUN 42gr MAX LOAD. 8 3/8" Barrel.

Sean,
I have shot at 200yds with the 270 gr bullets and they went right to what I was aiming at with a little hold over. Open sights.Now I load them faster with LIL-GUN powder. Back then I was using No.9 powder and have a scope now too.

I know JRO45, but I can't even get to 1800. I'm going to try to call S&W today and ask them and see what they say. Even Sierra says that's on the slow side.

JRO45, can you do me a favor? Or any of you with Model 500's for that matter? Can you guys measure the cylinder gap on your guns and tell me what yours come out at? Also, measure the diameter of the cylinder(s) (at the exit end obviously).

The gap on my cylinder is right at .010 and the cylinders are all in the .497-.498 range. A fellow at Sierra and I have been conversing back and forth and we've both come to the conclusion that I may be losing pressure due to the large cylinder gap (the one they have is about half of that). If any of you guys could take the time to get the measurements off of your guns it would certainly be appreciated. I'm also going to call S&W, I just haven't had a chance yet this week. Thanks in advance.

Regards,
Tom