ASSRA Forum - Shiloh 40-70 barrel groove diameter ?

ASSRA Forum › General › Reloading the Single Shot Rifle › Shiloh 40-70 barrel groove diameter ?

(Moderator Group: Moderator)

‹ Previous Topic | Next Topic ›

Page Index Toggle

Pages: 1

Hot Topic (More than 10 Replies)

Shiloh 40-70 barrel groove diameter ? (Read 383 times)

bullshop Senior Forum Member Offline Posts: 324 Joined: Sep 14^th, 2017	Shiloh 40-70 barrel groove diameter ? Apr 5^th, 2026 at 5:32pm	Print Post
	Anyone know what barrel groove diameter is used in Big Timber Shiloh 40-70 rifles?


	IP Logged

1Hawkeye Senior Forum Member Offline Posts: 256 Location: South end of Northern Virginia Joined: Jun 29^th, 2019	Re: Shiloh 40-70 barrel groove diameter ? Reply #1 - Apr 6^th, 2026 at 7:44pm	Print Post
	I don't know about the .40-70 but my .40-65 is .408" and I'm sizing to .410" You should slug the bore just to be without a doubt.


	IP Logged

ndnchf Frequent Elocutionist Offline Posts: 1119 Joined: Mar 6^th, 2014	Re: Shiloh 40-70 barrel groove diameter ? Reply #2 - Apr 7^th, 2026 at 7:17am	Print Post
	My 1990 built Shiloh .40-70 BN is .408".


	IP Logged

GT Frequent Elocutionist Offline Posts: 2342 Location: Northeast Wyoming Joined: Jun 28^th, 2015	Re: Shiloh 40-70 barrel groove diameter ? Reply #3 - Apr 7^th, 2026 at 12:09pm	Print Post
	I have a take-off Shiloh barrel for one of my projects, it slugs .408"

	"To invent, you need a good imagination and a pile of junk" T. A. Edison "The trouble ain't that there is too many fools, but that the lightning ain't distributed right" M.T.
	IP Logged

bullshop Senior Forum Member Offline Posts: 324 Joined: Sep 14^th, 2017	Re: Shiloh 40-70 barrel groove diameter ? Reply #4 - Apr 7^th, 2026 at 1:55pm	Print Post
	Thank you all ! I assumed .408 but wanted to be sure. This is for a bullet order that the customer didnt know what his groove diameter is on a 40-70 Shiloh rifle. I am cautious with 40 caliber BPC rifles because vintage 40 cal rifles seem to be .403".


	IP Logged

marlinguy Frequent Elocutionist Offline Ballards may be weaker, but they sure are neater! Posts: 17887 Location: Oregon Joined: Feb 2^nd, 2009	Re: Shiloh 40-70 barrel groove diameter ? Reply #5 - Apr 7^th, 2026 at 2:23pm	Print Post
	bullshop wrote on Apr 7^th, 2026 at 1:55pm: Thank you all ! I assumed .408 but wanted to be sure. This is for a bullet order that the customer didnt know what his groove diameter is on a 40-70 Shiloh rifle. I am cautious with 40 caliber BPC rifles because vintage 40 cal rifles seem to be .403". Almost all my vintage .40 caliber single shot rifles are around .410"-.411" groove diameters. Most the modern barrels I get are .408" grooves.

	(You need to *Login* or *Register* to view media files and links)
	IP Logged

oneatatime Frequent Elocutionist Offline Posts: 4385 Location: Rocky Mountains Joined: Oct 30^th, 2011	Re: Shiloh 40-70 barrel groove diameter ? Reply #6 - Apr 7^th, 2026 at 3:18pm	Print Post
	Just curious, what were Winchester's barrel dimensions for the .405 Winchester?


	IP Logged

George Babits Frequent Elocutionist Offline Posts: 1142 Joined: Sep 27^th, 2012	Re: Shiloh 40-70 barrel groove diameter ? Reply #7 - Apr 7^th, 2026 at 4:09pm	Print Post
	Really, there are two very simple ways to find out. First is to simply slug the barrel yourself; and second, just call Shiloh and ask them. Both ways are much better than seeing what others think or have found with their rifles. For instance, my original 40-70 Sharps has a .414 groove diameter, way larger than anything I have ever found in books. George


	IP Logged

bullshop Senior Forum Member Offline Posts: 324 Joined: Sep 14^th, 2017	Re: Shiloh 40-70 barrel groove diameter ? Reply #8 - Apr 7^th, 2026 at 11:55pm	Print Post
	oneatatime wrote on Apr 7^th, 2026 at 3:18pm: Just curious, what were Winchester's barrel dimensions for the .405 Winchester? I am pretty sure the 405 Win had a .412" groove diameter.


	IP Logged

bullshop Senior Forum Member Offline Posts: 324 Joined: Sep 14^th, 2017	Re: Shiloh 40-70 barrel groove diameter ? Reply #9 - Apr 7^th, 2026 at 11:58pm	Print Post
	George Babits wrote on Apr 7^th, 2026 at 4:09pm: Really, there are two very simple ways to find out. First is to simply slug the barrel yourself; and second, just call Shiloh and ask them. Both ways are much better than seeing what others think or have found with their rifles. For instance, my original 40-70 Sharps has a .414 groove diameter, way larger than anything I have ever found in books. George I cant use a phone because of severe hearing loss. I also dont have the rifle so cant slug the barrel. I do have positive experience here getting questions answered so this is a good choice for me.


	IP Logged

bullshop Senior Forum Member Offline Posts: 324 Joined: Sep 14^th, 2017	Re: Shiloh 40-70 barrel groove diameter ? Reply #10 - yesterday at 12:03am	Print Post
	George Babits wrote on Apr 7^th, 2026 at 4:09pm: Really, there are two very simple ways to find out. First is to simply slug the barrel yourself; and second, just call Shiloh and ask them. Both ways are much better than seeing what others think or have found with their rifles. For instance, my original 40-70 Sharps has a .414 groove diameter, way larger than anything I have ever found in books. George That is interesting because the same customer says he also has and original vintage 40-70 Sharps he also wants bullets for but again he does not know what the barrel groove diameter is on that one either. Maybe if I get him some bullets for his Shiloh he can try those in the original and learn something, maybe good maybe bad.


	IP Logged

sharps4590 Full Member Offline Posts: 113 Joined: Mar 24^th, 2016	Re: Shiloh 40-70 barrel groove diameter ? Reply #11 - yesterday at 6:50am	Print Post
	As you don't have the rifle in hand and apparently the customer does, can he slug his own bore? Seems that would eliminate all doubt. I don't remember what my Shiloh 40-70 SS slugs but I do know I size the bullets to .410.


	IP Logged

marlinguy Frequent Elocutionist Offline Ballards may be weaker, but they sure are neater! Posts: 17887 Location: Oregon Joined: Feb 2^nd, 2009	Re: Shiloh 40-70 barrel groove diameter ? Reply #12 - yesterday at 11:17am	Print Post
	Always surprises me how many guys who own guns and reload for them seem to have no concept of slugging a bore? Most don't even know how to go about doing it, or even what to slug the bore with.

	(You need to *Login* or *Register* to view media files and links)
	IP Logged

Lead Pot Full Member Offline Posts: 152 Joined: Nov 12^th, 2012	Re: Shiloh 40-70 barrel groove diameter ? Reply #13 - yesterday at 11:59am	Print Post
	My Shiloh .40-70 is .400 bore .408 groove. I wouldn't worry if the lead projectile is a couple thousands too small in diameter. When the powder is lit it will be groove diameter


	IP Logged

bullshop Senior Forum Member Offline Posts: 324 Joined: Sep 14^th, 2017	Re: Shiloh 40-70 barrel groove diameter ? Reply #14 - yesterday at 10:37pm	Print Post
	Mr. Leadpot Sir it not on subject but I find your picture very interesting in the variation in lead angles of your different chamber castings. Some with none at all and some with a long gentle angle and everything in-between. That is just very interesting to me and shows for certain that each rifle can be very different and the ammo for each must be different as well, no one size fits all. On some of my bullet auctions I offer choice of diameters within a range such as in 50 caliber from .500" to .518" in .001" increments. At times I will receive payment for an auction that offered diameter choice but no choice was selected. When I contact the customer to ask what diameter they wanted the answer is ," you know 50 caliber you dummy "


	IP Logged

Page Index Toggle

Pages: 1

‹ Previous Topic | Next Topic ›

« Board Index ‹ Board Top

Top

ASSRA Forum » Powered by YaBB 2.6.12!
YaBB Forum Software © 2000-2026. All Rights Reserved.

Valid XHTML

Valid CSS

Powered by Perl

Source Forge

Page completed in 1.2917 seconds.