40-90BN and paper patch

[Michael Johnson]

This is my first post on this forum so be gentle. I have 20 years of experience with BPCR's 45-70, 45-100, 40-65, and 50-90. Most of that has been with greasers. Three years ago Stephen Borud sent me some 50 cal bullets for paper patch and that got me off on the paper patch track. So now I have some experience with the 50, but most of my trials have been with my Shiloh LRE in 45-2.6. Now seeking to be completely humbled I have an order with Shiloh for a Paper patch 40-90BN. Initially this was meant to be a hunting rifle (Business rifle, 28 inch round barrel) then I started to think about something for BPTR (Shiloh No.1 with a 32 inch heavy round barrel). I ordered 100 cases from Rocky Mtn Cartridge when I heard they might be going out of business. I already have a ton of Starline 45-2.6 cases for my LRE. I figured I could reform them into 40-90BN. Because I thought a dedicated PP chamber was in order my initial thought was to have Shiloh do an Orville chamber with the 7 degree leade. But after reading a lot both here and on the Shiloh sight now I am not so sure.This gun will not be built for a couple of years so I unfortunately have way too much time to think about this.I do have some RCBS dies for an original chamber (.403 bullet) and will tell you that it is extremely easy to run an annealed Starline 45-2.6 case up and come out with a 40-90BN case. So no reason to pay Buffalo arms an extra buck per case for the pleasure. I am now leaning toward the standard Shiloh chamber which based on my 45-2.6 experience is already pretty tight. 0.480 at the chamber neck. I do have two questions. 1) does anybody here shoot Orville's chamber competitively and successfully. and 2) is there any compelling reason to have Kirk cut a 7 degree leade? As a target rifle I am planning on wiping between shots so some of the special fouling concerns with this cartridge are not that concerning. Thanks for any provided info and I am sure it will generate more questions. - Mike

[Don McDowell]

Best I can tell you is 1f and a lot of it. The one thing the 40-90 will tell you right quick is if you don't have enough powder and compression it will foul really quick.

[Michael Johnson]

Best I can tell you is 1f and a lot of it. The one thing the 40-90 will tell you right quick is if you don't have enough powder and compression it will foul really quick.

I use 103 grains of Swiss 1Fg with my PP 500 and 550 grain loads in a 45-2.6. I wipe between shots so I am not terribly concerned about fouling. Bigger concern is which chamber and why, also questions about the advisability of the 7 degree leade. I am leaning towards the standard factory chamber because of all the negative comments about Orville's chamber on the Shiloh forum. His chamber makes sense if you are trying to duplicate a historic firearm. I have a hard time reconciling all of the work that has been done in the last 60 years by modern rifleman against that which was done by a few individuals from 1870-1890. I am not trying to diminish the history only trying to recognize all of the many modern contributions. I am also looking at a 1/14 twist to handle 420 grain bullets to the 1000 yard line. I know what it is like shooting a 40-65 with a 1/16 twist at Silhouettes on a windy day past the turkeys.

[Don McDowell]

I think that a standard chamber reamer with the 7 degree lead built in might be a good thing. It sure works well in the 44-77 anyway.
This 40-90 will foul very quickly and cause a bunch more trouble than the straight cases. Not sure of the twist in this rifle I'm assuming 16 and it shoots to 1000 well, with the 415 gr money bullet. But with the 94 grains of 1f, getting squeezed thru that iddy biddy 40 caliber hole, hard bullets are the order of the day. 16-1 maybe a bit on the soft side. If this rifle had a heavy barrel on it I would probably shoot it more, but as it it barely tips the scale at 10 lbs, and shooting a match with it makes for a long day. I believe your heavy round barrel will be a bunch more comfortable to shoot.

[Distant Thunder]

"Now seeking to be completely humbled..."

Well you've pick a good cartridge to accomplish that!

My first BPCR had a standard greaser chamber in .40-90 SBN. It was not the best cartridge to start out with and I knew less than I do now after almost 30 years of loading and shooting these rifles. I never really got anything close to target accuracy with it with either GG or PP, but I got it as a hunter. Today I am sure I could make it work for that purpose. I had it rebarreled to .40-65 and it is sooooo much easier to work with. It still has a GG chamber but I shoot a 2-diameter PP bullet in it and couldn't be happier with the rifle. Accuracy is very good.

I think you will find that the other cartridges you've loaded, the .45-70, .40-65 & .50-90 are a piece of cake compared to the .40-90 SBN. You should get whatever your heart desires though.

If you look at match results from all over the world for the past 20 years I don't think you'll find many .40-90 SBN at or even near the top, especially on a regular basis.

Orville chamber is very popular these days and I have no doubt it allows for easy shooting of PP bullets. Those I know who have rifles chambered with that design are happy with it. I don't see it winning any matches for those I know. So I have opted to stay with Shiloh's standard GG chamber for my next rifle. Maybe I'll try a 7 degree lead in the one after that.

Someone will have to explain to me how that 7 degree lead starting from the outside diameter of the case mouth and tapering into the bore is a good thing accuracy wise. To my thinking that is a huge area that a bullet must bump up into and then have to be squeezed back down from .472" diameter to the .450 bore and .458 groove diameters in a .45 caliber.

I don't know what the dimensions are in a .40 caliber PP chamber with the 7 degree lead, but the idea would be the same. The bullet is expanded to the same diameter as the outside of the case neck and then forced into a much smaller hole! Make me understand how that is a good thing?

Again, it is a very popular chamber design and it's an old design. I'm just the kind of guy who has to understand (and see) how something works before I can put the hopes and dreams for my next rifle on the line. It's not a small investment in time not to mention money.

If you want to shoot in long range BPTR matches and be competitive go with a .45-90 or .45-70 (you want conserve powder) and the standard Shiloh chamber. You can shoot GG or PP and win matches. Myself and others have done that and are doing that now.

If, however, you want a .40-90 SBN you should do so and you should go with the chamber design and twist rate that have the best chance of getting you where you want to be. That is how I answered the same questions I had on my soon to be Shiloh .44-77. Just be honest with yourself and choose what gets you where you want to be. Piece of cake!

[Eric Johanen]

It is a matter of choice. I use standard Shiloh chambers in my target rifles and they shoot very well with either grooved or patched bullets. My M1877 is to be chambered with Brent's design and should do exactly what I wish to accomplish with it. When I ordered my 44-77 I went with Orville's chamber for ease of loading paper patched bullets for a traditional hunting rifle. Very good results on paper and steel at reasonable ranges. Just a Hartford front and a Lawrence rear sights. Shoots well to 400 yards. I chose to make it a hunter not a target rifle. I have never mounted targets sights on it so really do not know how well it performs at long range. Again, not the intended use for this rifle. Really have to get it on paper at 500 to see what is happening as I have had not had good results at that range (More to do with my eyes than the chamber.) I made my choice and am pleased with it for it's intended purpose.

[Distant Thunder]

Eric,
You're having way too much fun with that rifle!
Oh, and thanks for helping to rekindle my desire for a .44-77, I owe you one.

[Kurt]

Michael.

I will put my experience about the Orville type chamber.
I do not use Orville's chamber for match work but I do have one rifle with one and it shoots well.
Most of my rifles have chambers I cloned from Chamber casts made from originals, Sharps and Remingtons. The Original Sharps chambers I was able to get a cast from had much flatter throats than Orville's 7 degree. Dave at PT&G measured them at 3 degrees but I told him when I sent my print in to have a .45-2.4 reamer ground that I want the 5 degree/1.5 deg. compound and even this makes it a very long throat.
I had CPA build this rifle and I chose a Douglas premium 30" barrel and had it build for the silhouette matches and long range.
When I got this rifle I had a short time testing it on the 200 yard range and I found out right quick that this rifle was going to do well. I got word that there was going to be a Midrange shoot at Wisconsin Rapids for getting ready for a Lodi warm up so I packed my gear and got my Wife out of bed at 3:30 AM and made the trip up to shoot Arnies match just to see if this rifle will hold up at a longer range. I took 10 shots from the 600 yard line and I don't remember if Jim was pulling my target or not but I just shot for a group to see what the rifle and my best load to date will do. Carol said bring it down 1.5 minutes I said no I want a ten shot group on paper. After the 10 shots fired I said OK I will drop it 1 1/2 and I took three more sots but time ran out to get more in. But when I went to the pit those three shots were what I call a clover leaf, they cut and that group above I could almost cover with my hand with one at the thumb.
I used this rifle starting my way on the silhouette range I just started to shoot at Alma Mich. and with this rifle I shot my way into the AAA by the middle of the second season. It also put me inside the top 14 at the Q and 3rd at the MT 1000.
With this long post I just wanted to let you know that a long funnel type throat is capable of shooting and shooting quiet we.
The .45-90 is more than enough rifle for the iron critter matches so I had a mother CPA build that has a 4/2 degree compound throat in it and I will find out next season it it will shoot

   

[mherth]

Dual diameter PP bullets for standard chambers, compound leades for tight chambers, etc. My hair hurts. How about a bullet/chamber/leade combination that automatically adjusts for wind deflection?

[Kurt]

Been working on that Mike..........but I can't get the Gyroscope small enough to fit the rifle bore...............