40-90BN convertibility.

[Skywagon]

Can a 40-90 bn be easily converted to 40-90SS.

[kenny s]

nope. I have an original 40 90 sbn and had , because of a chamber problem, re sleeved and rechambered to 40 70 SS. It worked.
the original bore is not touched, and the gun lettered and is marked for a 40 70 .
however, because of the cost, I would think of re barreling instead of re cambering on a new gun.

[Don McDowell]

No it can't. The 40-90 SS cartridge has a much smaller case and rim diameter. Rebarreling and rechambering, along with another extractor is the only way to make that change.

[bobw]

Can a 40-90 bn be easily converted to 40-90SS.

Why would you want too? bobw

[kenny s]

I should have made it clear too in my answer. you Can't rechamber it to SS from bottleneck 40 90.
I know the 40 90 is a hard case to work with, but put on a new barrel. it will be right from the start.

and as a note. After all the work on the original 74, rechambering etc. $$ I still bought a new Shiloh in 40 70 SS and put the
original in the safe. I would not do it again.....
Ken

[Skywagon]

I’ve got a Shiloh 1869 in 40-90bn. I’ve tried several different powders and several different bullets from Montana Bullets. For the last year nothing I’ve used has given acceptable accuracy. It’s time to go down a different road and I’m just looking for options. I see that there is a 44-77 barrel on gun brokers or I may send to Shiloh and have them install a 50-70 barrel.
Thanks for the replies.
Gerry

[Don McDowell]

Might be the bullets giving you accuracy problems?
I have no accuracy problems in the 40-90 shooting 94 grains of OE 1f, in cases prime with rp 9 1/2 primers,, and topped off with a fiber wad, and a dry lubed felt wad under either a .400 diameter 360 gr bullet wrapped in 8 lb paper, or a .396 415 gr bullet wrapped in the same 8 lb. paper.
Bottle necks need a full case of powder with nothing of the wads or bullet below the base of the neck, and keeping the powder level above the base of the neck helps.

[Skywagon]

I followed all the advice you gave over a year ago Mr.McDowell. I’m thankful for it. But I believe it is time to try something different. Your more than welcome to the barrel once it is removed.
Gerry

[Don McDowell]

Well you obviously didn't other wise you would be shooting groups like this at 500 meters.

[77 sharps]

The .40-90 BN can be very accurate but it can be agrivating. If you are wiping or even blow tubing, it should shoot very well. The two pieces of advice I would give are; 1F powder ONLY and NO COMPRESSION!!!!! 0.010” compression can cause problems.

[Skywagon]

Your right Mr.McDowell. It has to be me not the rifle. The rifle is a Shiloh Products Inc. New model 1869. As I understand it these are pre Farmingdale rifles. They are highly coveted by marksmen for there known accuracy. This particular rifle strikes the primer way off center and on occasion even with a clean chamber the breach block will not drop allowing a round to chamber. 1F Goex & OE filled the case to the bottom of the neck and no compression. I also filled the case half way up the neck and compressed so the fiber wad and bullet are still retained in the neck only. I tried everything in between those two. Thanks for sharing your picture.
Gerry