I just got my order from midway that was supposed to be Starline, but the headstamp is Buffalo Bore. doesn't bother me except that I went to seat a primer and it seats extremely deep. I then fired the emptycase and the primer slid out past the case head, but not all the way out. has anyone had this problem?

I've never had that problem. Must be a bad batch, go ahead and send them back and insist on getting your Starline brass.

I tryed a large rifle primer and it seated normal and didn't come out when I fire the empty brass.

It's not supposed to take large rifle primers. It's going to cause you problems if you continue to use lr primers in them. You'll get some erratic loads because of the primers.

There isn't enough pressure created by just the primer without a powder charge to cause it to grip the primer pocket. That's why it backed out. Use Large Pistol primers in the .475.

the large pistol primers seat very very deep. it's definately not supposed to be that deep. I'm just going to send the brass back and tell them to give me the right brass

Send the brass back if you feel you should, but Starline produced the Buffalo Bore cases.

The LP primers seat deep and I have yet to have a problem with them, nor has anyone else I know who shoots this round; not even John himself. John recommended LP primers back in the day when he was cutting down .45-70 cases for .475 brass.

Work with it some and get a bit more experience before getting all flustered.

Ms. Hitman is correct on every point.

Ya, what he said.

Starline makes the brass for Buffalo Bore.

When the 475 Linebaugh was first made, Mr. Linebaugh cut down 45-70 cases. If you used Win cases, then the case walls were thin enough that you didn't have to inside ream them.
When loading the cut down 45-70 cases, I used CCI LP mag primers and never had a problem.

Try measureing the depth of your case's primer pockets and then compare to a rifle case.
It is possible that the cases were made wrong, but you might check them first to save yourself the hassle of sending them back.

A buddy of mine showed me a trick years ago. He said that he could get high pressure signs(a flattened primer) with just a primer in an empty case. I don't remember which case or primer, but the primer was ironed flat.

I went and measured some different cases with a dial caliper. I only measured 1 of each to get an idea of what things looked like.
Win 45-70 .128"
BBA 475 .129"
Hornady 475 .129"
Hornady 480 .122"
Win 45 Colt .121"
Rem 44 mag .122"
Starline 500 S&W .129"
Win 30-06 .128"
Rem 30-06 .128"
Rem 30-30 .130"

I measured the cup on CCI primers
Rifle .126"
Pistol .112"

I don't have any Starline headstamped 475 brass, but I would guess that it has a large rifle primer pocket like the BBA and Hornady brass does.

I'm also of the opinion that the primer pockets are probably made for large rifle primers. Furthermore, I have use large rifle primers in pistol cartridges and they don't necessarily cause high or erratic pressure. In fact 460 & 500 S&W cases are routinely loaded with large rifle primers.

OK I mesured some rifle brass pockets and I'm getting .129
This pistol brass is at .131.
If that sounds about right let me know and I'll use the brass. I just got concerned that this was too deep, but if it's normal for this caliber and safe, I'll keep it.

The parent case is the 45-70 made for the LR primer but don't use them. Use a LP primer and a LP mag primer for the slow powders. The primer will be .015" below the case head, normal, so don't worry. A fired case will have the primer level with the case head.
Only 2 things will back the primer out; An empty case fired or way too light of a load. A few gr's of fast powder to turn the thing into a pop gun will not let the case go back to the recoil shield and keep the primer in.
I would also check the headspace on the gun, it should be about .010".
Two bad things with the LR primer is the high pressure generated and most handguns do not have strong enough mainsprings to reliably fire them. It takes a 30# spring. A low poundage spring can cause hangfires, failures to fire and poor accuracy. THE .475 CASE IS TOO SMALL FOR LR PRIMERS no matter what is said here, you can get into trouble fast using them.

Use the LP primers only. bfrshooter is correct, you can run into several problems by doing otherwise.

well, I tryed the 475 linebaugh brass with the pistol primers and there was no problems. I tryed a load with 400gr speer bullet at 1200 fps and got a 10" group at 50 yards. once I figured out the best way for me to focus on the sites, I got way better groups. A load of 8.5gr of Trailboss behind a 325 gr bullet got me a 5 shot group of 2" at 50 yards with iron sites. Now that I am learning to shoot this BFR more accurately, I'll have to go back to the range with some of the hunting loads, (400 gr @1200 fps), before deer season.

The Trailboss 8.5 gr load is supposed to be pushing a 370 gr cast bullet at 825 fps. I'm using 325 gr copper plated lead hp bullets with this load and estimating about 861 fps. do you think a bullet of this weight at this velocity would be enough for deer?

Also, I realize that all experimental loads should be worked up to, but ...
The COL for the 370 gr bullet with 8.5 gr of trailboss is 1.770. I know my BFR can take at least a COL of 1.850. With that much more case capacity and a lighter bullet, do you think it would be safe to go up to 9.5 gr?

Quickload doesn't have Trail Boss in it, but your load sounds like it is very mild and on the low pressure side of things.

I think that with light powder charges, keeping the bullet seated shorter might help to keep the combustion more uniform.

I looked at the Hodgdon site for 475 data.
http://data.hodgdon.com/cartridge_load.asp
They show the 8.5gns Trail Boss with 370gn LFP going 824fps at 27,500psi, which is well below the max pressure for the 475 Linebaugh.
With just looking at general comparisons to other loads, you should be able to go another 2 or 3 grains and still be under the max pressure.

With that big heavy bullet, 825fps should work well for deer. I think that BFR Shooter has killed deer with a cap-n-ball 44 revolver. That would be much smaller than your 475 plinking loads.

You could adjust the load up and down until you find where it shoots the best, then load up a pile and go blast Bambi.
Let the caliber and bullet weight do the job and shoot what's comfortable and accurate.

Gohip, make that BFR HAPPY by going to 25.5 gr's of 296 and the Federal 155 primer with the 400 gr Speer. Mine has done 1/2" and 9/16" at 50 yd's with the Hornady 400 XTP. I get close with cast boolits with 5/8" average. 296 it THE powder with HS-6 running second for lighter loads.