Rossi 92 45 Colt inaccurate with cast

[hornady308]

I have an M92 Puma with a 24" oct barrel in 45LC that simply will not shoot cast bullets accurately at 100 yards. Over the last 4 years, I've tried the following cast bullets: Saeco 200gr swc, Lee 452-200-rf, Lee TL452-230-tc, Lee 452-255-rf, Lyman 454485 & 454424, NOE 454-255-HP, Lee 452-300-rf. I've tried bullets sized at .452 and .454, but neither has worked. I finally broke down and bought a box of Hornady 250 XTP hollow points, and they worked great. My bore slugs .451 and the rifle looks new. I've tried slow loads, hot loads, soft and hard bullets, slow powders, fast powders, etc. I've cleaned the bore several times with Barnes CR-10, but leading has been light. I have another Rossi in .44 Mag and it is very accurate with every cast bullet I've tried. Any suggestions?

[DougGuy]

Might want to do a pound cast and compare the results from both rifles. Something in there is blatantly amiss..

[Ed Barrett]

What do you consider good accuracy at 100 yards for 45 colt?

[hornady308]

This is what I call accuracy at 100 yards:


But, this is typical of what I get with cast at 100 yards:


Just a bit of a difference. I would be satisfied with 3" groups at 100 yards. That's about as far as I'd shoot when woods hunting. My R92 44 will easily do 2" at that distance.

[hornady308]

Tried a new load today: Lee 452-300-rf, sized .454, with 24gr H110 and a CCI 350 primer. Four of five shots went into a group of 3.8" at 100 yards, but a flier opened the group to over 6". It seems almost every group shot from this rifle has one or more fliers. At least this load shows some promise. Of course, I have no need for this much power considering I only hunt whitetails.

[DougGuy]

That's actually a dangerous load if the boolit is seated out long in the bottom crimp groove. 23.0gr should be MAX for H110 seated out long. You are seating deeper, in the top crimp groove and loading 24.0gr of H110? I don't know where you got this load but I am fairly certain you won't find it in any printed/published loading manual because it is well up into the .454 Casull pressures.

[hornady308]

Current data on the Hodgdon website shows a max load of 24gr H110 with a 325gr cast bullet. My bullets weigh less than that by quite a bit.

[nekshot]

I have a gun that despises cast also, but on yours I would clean up the crown and fire lap it. Maybe the barrel is tight under some dove tails or something that sizes the boolit down too much for the rest of the jurney down the tube.

[DougGuy]

Current data on the Hodgdon website shows a max load of 24gr H110 with a 325gr cast bullet. My bullets weigh less than that by quite a bit.

Mine go 320gr checked and lubed, Lyman #2 alloy. The data Hodgdon lists is for a cast PB not a GC boolit. What is your COA measurement? Afaik, 1.680" will not feed in the Rossi unless you modify a few things.

These are seated to 1.650" COA, and they are in the bottom crimp groove. I doubt they would feed in a factory stock Rossi as assembled.

[gon2shoot]

Tested a Rossi today, (Lee 255 RFN 17gr of 2400), 3 inch group with CCI primer, 1 1/2 inch with Win. primer. 10 shot string using starline brass, homespun lube.
Target at roughly 80 yds because 100 yds is under water.

[Bphunter]

I have a Uberti '73 in 45 Colt that shot exactly like yours...great with jacketed, terrible with cast and I tried a LOT of cast bullet combos. Then I discovered PSB. Lee 452-255-RF with 17 gr IMR4227 topped with 5.2 gr PSB, just enough for SLIGHT compression. Viola! Groups went from 6" to 1.5" @ 100 yards, 1100 fps over the chrony. Do your own due diligence on PSB before deciding if it's right for you. There is risk involved and you better know what you are doing. If you don't have Qload and a good chrony I wouldn't mess with it.

[hornady308]

I have the Lee 300's seated long and crimped in the bottom groove. They won't feed in the 92, so I load them as a single shot. At this time, I'm just chasing accuracy. It is my understanding that the gas check has a negligible effect on pressure. Hodgdon shows a max of 23.5gr H110 with a 335gr GC cast bullet.

[hornady308]

"If you don't have Qload and a good chrony I wouldn't mess with it."

I have the chrony, but not Qload. I wonder why a buffer would help when using a gas check bullet?

[Bphunter]

You got me there! I have the 300 gr Lee mold with GC, but I don't have any .45 GC's, so I shot them w/o and still had terrible accuracy even at 1100 fps. Pressure builds too quick for my '73 to get too excited about the 300 gr boolits, so I haven't pursued it.

[hornady308]

I don't really want to use 300+ grain bullets, I just tried them cuz nuthin' else has worked. I could try some 250-255 pb with buffer and see how it works. What do I have to lose? I didn't get a 45 Colt rifle just to waste money on copper bullets.

[DougGuy]

I have the Lee 300's seated long and crimped in the bottom groove. They won't feed in the 92, so I load them as a single shot. At this time, I'm just chasing accuracy. It is my understanding that the gas check has a negligible effect on pressure. Hodgdon shows a max of 23.5gr H110 with a 335gr GC cast bullet.

You may be okay with that seated out long. I know the Rossi is a stout action, they chamber them in .454 Casull, but that's also using Casull brass..

I am thinking there is something in the chamber or throat that is different from the .44 because just the diameter of the booilt wouldn't explain good groups in one barrel and lousy groups in another. Like the .45 has some unsupported space that allows the boolits to cant before they hit rifling. Something is up there, that's why I mentioned doing a pound cast with both rifles.

[Indio]

Have you checked the throat/free bore? I have a Marlin 45-70 im trying to squeeze more accuracy out of. I loaded a flat based pill backwards seating it deeper until it would chamber without binding. I found I can add a full diameter band ahead of the crimp groove 0.12 long using cases at max length.. I will be getting a mold made by accurate molds with this included. As I understand it a large amount of jump is a bad thing with cast pills

[DougGuy]

Freebore, as in smooth parallel bore the same diameter or half thousandth bigger than the boolit is a good thing for cast. It lowers pressure, increases velocity, and if it fits the boolit snugly, it keeps it squared up and aligned for when it hits rifling. Usually cuts groups too.

Un-supported free space like what you have with shooting a .38 Special in a .357 Magnum is not good.

[Larry Gibson]

Hornady308

Try the Saeco or Lee 200 gr bullets cast of COWWs + 2% tin or #2 alloy sized .452 and lubed with a soft lube such as 50/50 or BAC over 6.8 - 7.3 gr of Bullseye. Has been an excellent load in numerous SAAs, carbines and rifles in 45 Colt. That includes a Rossi 24" barreled rifle.

Larry Gibson

[Indio]

Freebore, as in smooth parallel bore the same diameter or half thousandth bigger than the boolit is a good thing for cast. It lowers pressure, increases velocity, and if it fits the boolit snugly, it keeps it squared up and aligned for when it hits rifling. Usually cuts groups too.

Un-supported free space like what you have with shooting a .38 Special in a .357 Magnum is not good.

Maybe freebore wasn't the correct term to use, the projectile I used to check the unsupported jump was sized .463, my loaded projectiles are .461 and my bore slugs out to .459. I dont think an totally unsupported 0.12 jump is helpful for accuracy, or at least is worth removing to test if accuracy improves IMO