I finally made it out to the range today with the “improved” John Ross model. It came to me with 0.4985” cylinder throats. I sent the cylinder to Jim Stroh to get it reamed out to 0.501 this past winter and I received it back a couple weeks ago. All cylinders measure right at 0.501 – the minus plug can be pushed through with a little force. I fired 3 groups of 5-shots each and all I’ll say is I’ve never before ever fired 3 bug hole groups back to back. I went from 1+” to 2 inch groups (open sights - last summer) at 25 yards to under 0.4” today. Today was 40*F and had maybe a 15mph quartering/crosswind and it wasn’t nice at all out there. I was shooting 440 grain HC, IMR-4227 powder at 960fps and I was using a 2X scope rested. When I get my 2.5X8X32 Leupold later this month I’ll have go back to the range and see what the groups will be at 50 & 100 yards. Opening the cylinder throats made a huge difference to my revolver and I never believed a revolver could shoot this well - consistently. I've got a couple very good shooters but none have ever shot like this.

Pretty impressive accuracy. Don

I have the same gun but have not slugged it yet.

Did you measure the bore before you settled on the .501 throat dimension?

Do you think the open sight vs scoped test made much difference? Did you chrono the same load before and after the throat ream?

Thanks for sharing the info!

No, I haven't slugged the bore. I've only seen 0.500 & 0.501 diameter hard cast bullets for the 500S&W and those are the only diameters I've ever shot. The 0.501 throat will handle both diameters. I didn't know what, if any, improvement reaming the throats would provide me but I'm sure glad I had it done, as I've never shot consistent bug holes before with a revolver. When I shot 2700 with a revolver at 25 yards back in the day, I was just happy keeping all 10 rounds in 3”. Today, I was looking for and would have been very happy with consistent groups of 1" or a little less off a rest. A scoped revolver, rested will always shoot better for guys with old eyes, and I have old eyes. The 2X scope normally doesn't do much for me, as I can't see much for target definition, but a scope allows you to just concentrate on the X-hair instead of concentrating on the front sight for both vertical & horizontal spacing. Much easier. Using the ragged hole rear sight on my BFR's help on moving targets but I haven't shot any better groups per se. The scope helped but in my opinion wasn't the reason for these super small groups. I shot a lot of 45 Colt today through a Freedom Arms 97 using the same scope and never shot a 5 shot group under 0.4". I can do under 0.6” ocassionally with certain loads with the FA but so far I haven't done under 0.5” rested and scoped. I fired 30 rounds of 475 Linebaugh today looking for a decent load but couldn’t break an inch. Kept everything under 2” and some loads showed promise, so I'll work on those a little more. I’ve got a couple BRF’s that shoot mighty fine but they won’t shoot consistent big bug holes and seldom do I see groups under 0.6”. No, I never chrono this particular load before. I think as the weather gets warmer, this particular load might give a few more fps but should still be consistent. It will be the total ***** if next time at the range I shoot an inch or better with this load and I find out that today was just a fluke - I'm betting it wasn't but but but.

I have a JRS and mine measures between .499" and .500" with pin gages and shoots very well for me. Sounds like yours was just a touch tighter before opening it up.

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Tom

This is very interesting as I was going to open up mine as well.
7P's, Please let us know how they shoot at 50 to 100yds. Here is a question; You mentioned the load was 440gr@960fps with IMR4227. How much of that powder did you use for that low velocity? Did you use 50Special case?

My throats measure at .500 inch. I think the .501 does not go.
Impressive groups under 1 inch.

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NRA Benefactor Member

Well, I went back out today to duplicate those bug holes and the bugs matured and left home. Last time was a fluke but at least I had bragging rights for a week. Now I’m back to eating crow. Groups opened up to ¾” and better at 25 yards rested & scoped. I shot some nice 3 & 4 shot groups but was hard put to keep 5 touching. I only had two groups back to back that measured just under .8” and that was with HS-6. I tried N110, N120, IMR-4227 and HS-6. The HS-6 load was 15 grains behind a 440 grain hardcast that averaged 888fps. I only had 10 rounds of HS-6, as I didn’t think that powder would do diddly squat but it surprised me. Weather was perfect, so I don’t have any excuses. Opening up the cylinder throats helped my JR500’s accuracy a lot and I think a good revolver shooter could do a lot better with this revolver than I can. I had my scope set at 5X and it was an experience, as the X-hair danced all around that little 2" red spot on the target - my timing was terrible, as my let offs were at all points of the compass - I guess there's something to say about lower power scopes, as you don't see the movement your grip causes as you squeeze and then relax a little, so it doesn't play such a mind game with ya.

Tom C - did you mean a 500 JRH? If so, I have one of those from BRF and the throats on mine are 0.5005 and it shoots well also.

The IMR-4227 load was 28 grains - today it averaged 1,002fps with the 440 grain hardcast with bigger groups to boot.

7P's I really don't know what you're beating yourself up about. Legitimate 3/4" groups at 25 yds are excellent when shot off a rest or bags rather than from something like a Ransom rest.

I'd repeat what I've said before on this forum, people only brag about their exceptional groups, they seldom mention really poor ones which may really be the norm. No different than golf, who mentions the quadruple bogies?? No one, they just tell of the birdies or exceptional pars, right?

Personally I don't shoot my .500s from the bench. The range I belong to has nice concrete benches but they're too short for my height (6' 2") so off of sandbags, I'm hunched over and the arms are close to being in line with my back and all the recoil goes right to the elbows, so heavy loads are NOT fun. Don

I agree Don. The only way most people, which includes me, can shoot nice groups with any firearm is off the bench. Finding that right load is what’s difficult and time consuming. In my experience anyway, a scope or red dot greatly enhances your chances of shooting bug holes when shooting off a rest and even then it seems everything has to be just right, as some shots seem to break perfect but for some reason will go a bullet hole or two out of the group at 25 yards. In long range rifle shooting I attribute that to mishandling the rifle, ie too much cheek pressure etc. With the revolver I imagine it could be your grip. Never thought about it when I shot 2700 pistol, as the X and 10 ring where just over 3” and after a year or so it wasn’t a problem shooting perfect scores at 25 yards, in fact it was almost a given with a high X-count, but the 50 yard stage to me anyway, was always the impossible yardage to clean the target. I’ve read where people are shooting .5” groups at 50 yards with handcannons off the bench. All I can say is so far I’ve shot a couple 2-shot groups that might measure .5” but after the next 3 rounds the group always starts to expand and sometimes with open sights rested, I’ll have trouble covering the 5-shot group with both hands. I’ve got some very good loads for various revolvers & pistols that group at or under an inch at 25 yards using open sights and rested. Shooting off hand I normally can keep everything within 3 inches but there’s the occasional blocked sight that will open the group up to 5 inches or so. At 100 yards I’ve been known to miss the entire target and target frame – sometimes I thought the bullet must have went perfectly through another hole, as the sights weren’t that bad at the break but the guys shooting with me never have given me the benefit of the doubt – what doubt?

Another item I forgot to mention yesterday – I’ve previously posted that I’ve been using WLP primers with my 500 Smith reloads without any type of a problem. Ran into a big problem yesterday using AA1680 powder. I had 15 rounds loaded up, 5 each of 32, 33 & 34 grains of AA1680. 1st round the primer went off but didn’t ignite the powder – forced the bullet about 2” into the barrel and the unburned powder packed in behind the bullet and some was in the front of the cylinder. Tapped the bullet out, cleaned up the revolver and fired the 2nd round – same results. I’m pulling the other 13 bullets and will use large rifle primers for that powder in the future and I’ll probably just discontinue the use of WLP’s in the 500 Smith and just go with large rifle primers, as a hotter primer and a little more pressure may not be a bad thing after all.