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VenisonRX
12-28-2023, 02:50 PM
How consistent are the bores of the 50/70 rolling blocks? I know the bores of the sharps carbines are all over the place for various reasons. Without having a rifle yet is this one where the only way to have an idea is to slug it or would I be able to at least hedge my bet and likely use the Lee 450-515 bullet I already cast. I’d like to get into a rolling block but I’m not sure if it’s worth it for me if I’m walking into it knowing what I already do is very likely not going to work. The roller in question is claimed to be a trials rifle. So it’s that or a NY militia rifle.i wouldn’t be looking for pinnacle accuracy. Just something that a .515 bullet and 60gr of FF will be fine out to about 100 yards or so. Using the same ammunition for both rifles.

marlinman93
12-29-2023, 12:28 PM
How consistent are the bores of the 50/70 rolling blocks? I know the bores of the sharps carbines are all over the place for various reasons. Without having a rifle yet is this one where the only way to have an idea is to slug it or would I be able to at least hedge my bet and likely use the Lee 450-515 bullet I already cast. I’d like to get into a rolling block but I’m not sure if it’s worth it for me if I’m walking into it knowing what I already do is very likely not going to work. The roller in question is claimed to be a trials rifle. So it’s that or a NY militia rifle.i wouldn’t be looking for pinnacle accuracy. Just something that a .515 bullet and 60gr of FF will be fine out to about 100 yards or so. Using the same ammunition for both rifles.

When it comes to older rifles nothing is for certain. I would never load for one without slugging the bore first to see if my existing mold might work, or bullets could be sized down if need be.

BLAHUT
12-29-2023, 12:58 PM
You will need to slug the barrel ? 450/515 is a .45 cal. bullet ?? not a .50 cal. bullet ?? You could beagle the mold and get a little bigger .45 cal. size ? just not up to a .50 cal ??? Not Even in pure lead ?? IMHO The .450/515 in pure lead; I use in my 45/70 bear gun, at about 1200 FPS. Accurate out beyond 100 yds....

marlinman93
12-29-2023, 03:43 PM
You will need to slug the barrel ? 450/515 is a .45 cal. bullet ?? not a .50 cal. bullet ?? You could beagle the mold and get a little bigger .45 cal. size ? just not up to a .50 cal ??? Not Even in pure lead ?? IMHO The .450/515 in pure lead; I use in my 45/70 bear gun, at about 1200 FPS. Accurate out beyond 100 yds....

Might be reversed as Lee makes a 515-450 mold, and likely what he's got.

VenisonRX
12-29-2023, 05:44 PM
Yeah sorry I meant .515 diameter 450gr. The copy of the Lyman that drops a .515 bullet instead of .512. I’d definitely slug the bore to be sure. Was just curious if they tended to be pretty consistent and the odds would be in my favor of getting a rifle that would shoot a .515 bullet fine. Or if they were so inconsistent that I’d be pretty likely to have to essentially start from scratch with everything. Not looking for competition accuracy just casual shooting accuracy.if I ended up with a rifle that was too different then it is what it is. But I’d probably pass on it if that was probably going to be the case.

gunther
12-29-2023, 07:46 PM
Got s couple of 50 caliber Remington carbine barrels from Dixie about 1980. Put them on rolling block #1 actions. Had to rent a reamer to get them to 50 70. Never really checked for accuracy, but the Lyman 515141 was the only thing available at that time. Cases from Dixie, slugs loaded as cast of WW, hand lubed, 3f powder left enough room in the case to seat the bullet. At 20 yards the load took the back out of a 6 inch poplar. That's the whole 180 degree back splintered and gone.

Bad Ass Wallace
12-29-2023, 08:59 PM
My 50/70 likes either the Lee 515.450 (sized to 0.512") or my Paul Jones 0.512.520 which is shot 'as cast' and is simply the best. I did a chamber cast and determined the bore was 0.500/0.510".

https://i.imgur.com/7Rj84YXm.jpg

marlinman93
12-30-2023, 12:05 PM
I have old BGI and Winchester molds for .50 caliber that both drop bullets around 450 gr. but .519" bullets. They're too large for my .50 caliber barrels that are around .511"-.512" groove diameter. I think older barrels might be either the larger @.519" or the smaller @.512", so still need to slug to be sure. My recent purchase 1867 pistol slugs at .512"

pull the trigger
12-30-2023, 12:12 PM
Just get the rifle, youll figure something out. Dont forget about paper patching.

VenisonRX
01-01-2024, 06:11 PM
I have old BGI and Winchester molds for .50 caliber that both drop bullets around 450 gr. but .519" bullets. They're too large for my .50 caliber barrels that are around .511"-.512" groove diameter. I think older barrels might be either the larger @.519" or the smaller @.512", so still need to slug to be sure. My recent purchase 1867 pistol slugs at .512"

That little sharps of mine has been a big guessing game. It’s got the three groove barrel and was difficult to figure out. I tried two different methods. Slugging and then wrapping the slug with a steel of known thickness then subtracting that out as well as measuring from the bore end of the barrel in a few spots on the grooves and averaging to figure it out. The latter I don’t really trust the results from due to what looks like inconsistency in outside dimensions of the barrel. I settled on .515 as close enough. I think now that I’ve been shooting it awhile that .516 is the correct answer since I’ve been seeing a slight amount of leading. Just going to stick with it though. Its accurate enough and it’s not enough leading that a pass or two with some brass mesh won’t fix.

All of the rolling block talk now though is a moot point because my lovely wife spoke to Bill Goodman and ordered one of his special run rifles he had shiloh make him in 50-70 for our anniversary. Turns out she knows me better than I know myself. Really looking forward to it.

marlinman93
01-02-2024, 01:32 PM
Odd number rifling is always a bit tough to measure, but they do make dial calipers especially for this purpose. You can also measure from one land to a flat spot across the bullet and then simply add the depth of one groove to that to get a result.

VenisonRX
01-03-2024, 09:34 PM
I never thought about going about it that way. Seems simple enough. I’ll have to give that a try sometime.

varsity07840
01-04-2024, 06:01 PM
I have two single cavity Lee .515-450 moulds that won't cast bigger than .512. My two cavity drops them at a tad under .517 which is what I want for my .515 groove .50-70s. I dip lube them and then run them through a .517 sizing die to clean them up. Slugging/measuring a bore for groove to groove size is SOP for BPCRs, old or new.

HWooldridge
01-04-2024, 07:25 PM
https://www.google.com/imgres?imgurl=https%3A%2F%2Fwww.hommel-hercules.com%2FZoom%2Fklein%2F35441676&tbnid=HTVJyPF5f_TbcM&vet=12ahUKEwiQ-9nP8MSDAxVVH9AFHY88CaEQMygLegUIARD1AQ..i&imgrefurl=https%3A%2F%2Fwww.hommel-hercules.com%2Fen%2FShop%2F1031672107%2F3-point-micrometer-DIN-863-reading%253A-001-mm-prism-60Grad-MR%253A-80-95-mm&docid=0aYzlTKSP_nuWM&w=575&h=300&itg=1&q=3%20point%20v%20micrometer&client=safari&ved=2ahUKEwiQ-9nP8MSDAxVVH9AFHY88CaEQMygLegUIARD1AQ

3 point micrometer for 3 groove rifling measurement.

varsity07840
01-05-2024, 02:41 PM
How consistent are the bores of the 50/70 rolling blocks? I know the bores of the sharps carbines are all over the place for various reasons. Without having a rifle yet is this one where the only way to have an idea is to slug it or would I be able to at least hedge my bet and likely use the Lee 450-515 bullet I already cast. I’d like to get into a rolling block but I’m not sure if it’s worth it for me if I’m walking into it knowing what I already do is very likely not going to work. The roller in question is claimed to be a trials rifle. So it’s that or a NY militia rifle.i wouldn’t be looking for pinnacle accuracy. Just something that a .515 bullet and 60gr of FF will be fine out to about 100 yards or so. Using the same ammunition for both rifles.

Before you buy that roller, you may want to consider that .50-70 brass is very hard to find. If you do find some, you're going to pay a fortune for it. Right now there's 27 pieces on GB and the high bid right now is almost $4.00 a piece. You might be better off with a .45-70 TD.

hpbear101
01-05-2024, 08:48 PM
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The lee 450 grain bullet is a pretty close copy of the original, It shoots well in my Springfield 1868 Rifle and 1868 Cadet.

VenisonRX
01-06-2024, 10:09 PM
Before you buy that roller, you may want to consider that .50-70 brass is very hard to find. If you do find some, you're going to pay a fortune for it. Right now there's 27 pieces on GB and the high bid right now is almost $4.00 a piece. You might be better off with a .45-70 TD.

Actually I already have a bunch of 50-70 brass thankfully. Picked it up the last time starline did a run on it. I use some of it for my sharps conversion carbine which is why I was originally asking. To see if their bore size was consistent enough that I wouldn’t have to buy different molds or reset my dies for casual shooting. But I won’t be going with a roller now. My wife bought me a new shiloh shiloh in 50-70 so I will be getting a new mold or two and separating some brass out for that. I spoke to Kirk at Shiloh and I have a very good idea where to start based on the chamber and barrel dimensions he put in it. For my next rifle I’ll be going a completely different direction but that’s a long ways off.

VenisonRX
01-06-2024, 10:15 PM
[ATTACH=CONFIG]321760[/ATT

The lee 450 grain bullet is a pretty close copy of the original, It shoots well in my Springfield 1868 Rifle and 1868 Cadet.

I have that same mold. It works great in my 68 sharps conversion. I think it may be a tad undersized since I get a very small amount of leading but for how much and how I shoot it, it’s not an issue. Cleans out easy enough and shoots accurately enough for my purposes. Pretty low fuss bullet cartridge combo really. For the new rifle I’m going with something a little longer and drops at .510. The first one I’m going to try is the “Wackum” mold from BACO. It’s a 540gr but should do well since this rifle has a 1:22 twist.