454 SRH .."issues"...

[makicjf]

I picked up a 454 SRH with a 7 1/2 inch bbl, had it cut to 4 inches and moon clipped in an effort to make the perfect all around hammer. The issue I am having is with anything short of full throttle Ruger only 45 colt or 454 loads I'm getting leading ( significant leading) at 8:30 and 4:00 o'clock starting in the forcing cone and trailing down the bbl as I send rounds down range. Any load other than a Lee300 gc WWWD ( assuming its the GC and water drop plus full throttle pressure to obturate) leads. It is pretty accurate with the ruger only and 454 300 grain loads.

The SRH has big throats, a .454 bullet passes through with light pressure, and the bore was just about .451 with my ham fisted slugging/measuring. When the bbl was reduced, it was rethreaded and the forcing cone recut and I'm thinking the cone may be rough and I may have a thread constriction. I also get occasional lead spitting....
Does this sound like a candidate for Taylor Throating?
Jason

[High Desert Hunter]

That and firelapping, I would also try shooting some bullets with a .453 or .454 diameter to see how they do. How do Jacketed bullets shoot?

[5Shot]

What diameter lead bullets are you shooting at less than full throttle?

[DougGuy]

Unless you are just in the mood for experimenting, Taylor throating is only needed in worst case thread chokes. I don't know about firelapping a SRH, it may show a minimal improvement, and I say this because the stainless Ruger uses for these is some tough tough stuff.

Have you tried the tight patch method to detect choke? With a clean bore, if there is choke you will see a visible circular distortion where the front of the frame is. It's easy to see. If you patch a plastic or brass jag very tightly in the bore and push it toward the frame, when you get to the threaded part of the bore, you can very easily feel it tighten if there is a choke. If the tightening is minimal, firelapping may smooth it out and open it up, but with the SRH it will respond to firelapping much slower than a blued steel gun. If the cleaning jag stops, and you have to really push on it to get it the rest of the way through, this is severe enough to either rebarrel it, or Taylor throat it, because it's way more constricted there than firelapping will take out. If you do try and firelap one that bad, there is a good chance it can ruin rifling in the rest of the bore.

The guns that have .003" choke do respond well to Taylor throating, I have a Vaquero that was extremely choked, mine was down to .448" or less, I couldn't believe the amount of added force necessary to pound a soft pure lead ball past the choked part. Unbelievable that it would leave the factory choked that badly. It shoots very well now, no leading, and the point of impact for heavy boolits loaded ruger only max loads dropped 6" in 25yds after cylinder throat reaming and Taylor throating.

[makicjf]

I'll take a peak down the bore and see if I can see the ring...I have not appreciated one...and I've spent ALOT of time scrubbing this beast. I size all the 45 colt, 454 and 45acp that go through it to .454. The shorter the round, the worse the leading...eventually ending up with the lee 255 swc sized to .454 and roll crimped in a 45 acp over 6.3 of uniquecase keyholing 2 out of six after 4 or five clips. It shoots the RCBS 255 keith sized the same better , but still leads. 45 colt with the lee 255 rnfp, lee 255 swc or the RCBS 255 keith all ACWW shoot well from anywhere of 8.5 to 10 of unique, but still lead from just in front of the cone at 4;00 and 8;30 and trails down the bbl. I bought 100 45 acp hardball ( ouch ... buying a round hurt my pride) and ran them through. The bore stayed clean, but I got spitting every so often... groups where what I could expect from a stubby round in a long cylinder-3 - 4 inches from 25 yards , and minute of 1/2 an acetylene tank from 25 yards rapid fire DA. The leading with 45 colt did diminish a touch after that, or maybe I'm just wishing...
I don't recall a tight spot when I slugged the bore, but I'll pick up some .457 round balls or lead sinkers and re-slug . I don't appreciate a tight spot with a bore brush or with a t shirt on a cloth. Perhaps recutting the forcing cone would be a place to start if I can't identify a constriction?
Thanks!
Jason

[DougGuy]

All it takes is one part of the gun to be off and it shows up in other ways. After I did my cylinder throats and forcing cone on the .44 SBH, it quit spitting. I don't know if it was the throats more responsible for it than the cone but I am guessing it was the cone being it was short and rough with tool marks quite visible. Gone now, nice smooth 11° cut evened it up nicely.

If you have .454" throats, the forcing cone would need to be larger than for smaller throats, that just might clear it up.

[makicjf]

That sounds like a good plan! If it does not work, I'll go forward from there!
Thanks !
Jason

[DougGuy]

One other thing.. That is a Casull cylinder, right? So you have a lot of freebore that is MUCH larger than the boolit, so when the boolit exits the case mouth, there is oh .034" or greater of space around the sides of the boolit for it to go bouncing towards the cylinder throats, so now you got a boolit that might have half of it's bearing surface wiped completely off, going into the forcing cone. I don't know how much forcing cone improvement you will notice if this is the case. This effect is probably worse with the ACP case because it's shorter.

[High Desert Hunter]

That is a good point, if it is only happening with light loads in ACP brass. I had a SRH 454 for several years, mine wasn't cut for moon clips, so all of my light loads were in 45 Colt brass or in Casull cases, I shot a lot of Lee 255s up to light loaded 325s with no issues. Wish you the best of luck with this, I know how frustrating it can be.

[makicjf]

I thought about the short case, long cylinder, and you are right, the longer the bullet and the better it shoots. My hope is to reduce and or eliminate the leading with 45 colt. If i can shoot colt well, thats good enough. The combo of length and mismatch in throats vis a viz bore may be to much to overcome in the stubby case.. thats what the vaquero and 1911 can eat.
It can't hurt to 11 degree the cone and see if long 46 colt loads ,1.655, shoot without leading. If the 45 acp work, woohoo, if not no loss.
Jason

[DougGuy]

With the Lee 300 RF I seat to the bottom crimp groove in .45 Colt brass. Should be the same in your gun as seating to the upper groove in Casull brass, in both situations the boolit is into the cylinder throat a considerable bit. THAT is what will keep leading down and groups from spreading, and yes you are correct you would definitely notice forcing cone improvement with loads that put the boolit into the throat when they are chambered.

[makicjf]

I do as well, 24 h110 , 1.640 oal with a stout crimp and a lee 300 gc wdww is heaven...no lead, clean bore. The same bullet over 32 grains h110 ( can't remember the oal 1.77 something) is the hammer of thor and knocks over my steel... The RCBS 255 keith seats out longer than the lee 300 in a colt case, 1.655... It shoots well, too. I'll have the throat cut .
I see a ray of hope for standard pressure 45 colt loads...
Jason

[makicjf]

I scrubbed every bit of lead ( and could not find a constriction that I could see or feel) and then scrubbed it again. I shot 12 before work this A.M. of the RCBS 255 keiths from ACWW sized to .452 ( actual .453) and lubed with a lube of beeswax, Crisco, a shot of canola oil and a 1/4 tube of LLA in the mix) and did not get a spec of leading. Precision was not tested, but I got 12 solid hits COM on my steel from 20 yards double action. I'm wondering if I had created a build up of lead in the cone and just in front shooting 45 acp and the remaining deposits were causing the leading. If the leading DC's with the .453 bullets and not shooting 45 acp I'll be thrilled. I am going to have the forcing cone cut, but I *might* be on the right track!
Jason