Hi, I'm new to this forum and have gravitated here because I seem to enjoy reloading as much as hunting.

I recently had a custom 475 Turnbull 1886 made with most of the bells and whistles, and some of my own ideas. Came out fantastic - don't hate me but yes I do take it out and shoot it (a lot!).

The issue I am having is that the factory ammo I purchased when I picked the gun up is running about 2050fps for their 400 gr. Barnes TSX and I am having high pressure signs.

Specifically, the primers are flattened and the firing pin dent in the primer are cratered (seem to flow back into the firing pin hole in the bolt face).

Also, there are several marks on the brass from the bolt face.

Does anyone else shoot 475 Turnbull and have these pressure issues? Their "reduced loads" of 420gr gas checks at 1700 don't have any problems.

The brass the ammo is in is Jamison not the starline.

Does this look familiar?

Caused by worn firing pin hole in bolt of an 1892 .357. A gunsmith repaired this for me and now there is no cratering.

Aside from that wear-caused problem, there are so many variables in reloading, I can give only one comment:
In my Miroku/Winchester 1886 .45-90 shown below, Using Starline brass and ABW Kodiak heavy jacket FMJ 450 grain .458 bullets at 2150 fps, there are no pressure signs and accuracy is good. Grizzly Cartridge loaded this ammo and I have no details on the primer or powder used.
Conversly, in this same rifle, three brands of monolithic solids showed pressure signs including difficult extraction at just over 2000 fps; this was using H322 powder.

Have fun solving your problem and enjoy your rifle.

I have a 475 Turnbull based on a win 71,I have shot a fair amount of the 400 Tsx hand loads,@2050 fps there should not be a problem with pressure,if this is a new gun? I would send it back to Turnbull manufacturing & let them check it out,you might have a tight chamber? But that is just a wild guess,in mine I did have sticky extraction,I sent it back,the chamber got polished & it has been fine since,their after sales service is excellent.

If you have cratered primers, I believe the firing pin opening is too large. Have it checked and a bushing put in if necessary. As for the marks on the case head, that sounds like high pressure, and there are several things that can cause that. To speculate would be exactly that. I would have the chamber checked; it may be short, the leade too short for that particular projectile, etc.

Thank you guys,

Yes it is a brand new gun from them, I picked it up in Jan.

I do believe it is best to send it back to be checked out since it is new and was using the ammo they sold me with it.

A little disappointed that the 475 Turnbull cartridge was only running at 2050 fps(this was marked on the ammo packaging) for their 400 barnes TSX. This equates to 3733 ft-lbs at the muzzle.

I have a 26" barrel on it and the 475 turnbull cartridge was designed or promoted as producing 4000+ft-lbs or 2150fps with the 400gr bullet and mine shows pressure at 100fps less.

I feel for you,a new gun should be right the first time but however stuff happens,Doug's after sale service is really good & you will have no problems getting 4000 ftlbs of energy,& actually maybe a little bit more if you are a hand loader,I took mine out to the range yesterday,I was testing some Woodleigh's that I normally shoot out of my 470 NE @ 2150,I clocked them @1975 fps out of my 24" barrel,I would take this load to Africa for buffalo.

Doug should have bushed the firing pin I would think, and he is an excellent gunsmith. Cratering can result from a poorly bushed firing pin hole or from too much pressure. flat primers may or may not be an indication of pressure as it can be soft material, so that's always a maybe..

I would drop a grain or two then chronograph it. I would change powders, maybe primers, and the problem could very well be inferior brass, I have heard complaints on the brass your using form several sources btw... Marks on the case head are a indication of too much pressure for sure, end of story..

If you have a minimum chamber then you should get the same velocity but with less powder and that's a plus of sorts.

The important thing is to find out whats going on, its an investigation and all aspects need to be attended to..its a process of illumination, not just a maybe this or maybe that.

Might be a good idea to take this up with Doug, he will fix it properly that much I will guarantee..