454 Casull w/Hornady 300XTP

[Edster]

Ok here is my delima. I have a bunch of Hornaday 300 gr XTP, this is the one with the 2 cannelures. The max OAL listed for the 454 is 1.765" In order to get this I land up with the top of the brass right in between the cannelures.

If I seat to the bottom cannelure I will have an OAL of 1.865" so this is a NO GO.

If I seat to the top cannelure I get an OAL of 1.695".

My question is if I use the upper cannelure and the shorter OAL am I going to increase the pressure to the point that I should be worrying about it.

Looking at using H110 I believe the load I was looking at was 29.5 gr. I'm away from home and can't remember what the powder load was exactly.

[Ranch Dog]

It could raise it significantly. I took your cartridge length numbers with the 29.5-grain load of H110 through quickload. At 1.795", the powder is already significantly compressed at 107% of the useful case capacity. Decreasing the case length .100" increases the compression to 123% and bumps the pressure 18,000 PSI. So, yes, I suspect that the case length change is significant. Really, I wonder if you could seat they bullet at that OAL with that much compression behind it.

Do you have Hornady's data for the bullet?

[Edster]

Hornady actually publish bullet data, I've looked but haven't found any. I'm not at home so I can measure the bullet. I do know from some research that the cannelures are .325" and .430 " from the heel of the bullet. I am using Starline brass if that makes a difference.

[Ranch Dog]

Hornady actually publish bullet data, I've looked but haven't found any. I'm not at home so I can measure the bullet. I do know from some research that the cannelures are .325" and .430 " from the heel of the bullet. I am using Starline brass if that makes a difference.

Yeah, they have their prioritary data in their reloading manual but I don't have a copy of it though.

[Edster]

RD the manual is at the house and I won't be home till Friday. Funny thing is you are saying that at 29.5 gr it would be at 107% of case capacity and compressed. 29.5 gr is not the max load and there is nothing in Hornady's load manual stating that it is a compressed load.

[Rooster59]

Sounds like a call to Hornady Tech might be a safe bet.

[Edster]

Well talked to Hornady and they said that the 300XTP is not for the 454 Casull. Have to use the XTP Mag. XPT's are only good for velocities up to 1500 fps.

So I guess the XTP's are gonna have to get used for 45 Colt. Guess I am gonna have to work up a load for the Rossi.

I have a couple of boxes of the XTP Mags so I can still load the 454. Been looking at some Cast bullets, 340 gr. Might give em a try.

[joec]

Hornady calls for the following based on their current book.

Case length is 1.383 and using the 300XTP Mag 1.745.

[Ranch Dog]

Looking at using H110 I believe the load I was looking at was 29.5 gr. I'm away from home and can't remember what the powder load was exactly.

Hornady calls for the following based on their current book.

Case length is 1.383 and using the 300XTP Mag 1.745.

Thanks Joe, with those numbers and the OP's choice of H110, I ran it through QuickLoad and it spit out 30.7 as the max with the 300XTP/Mag #45235. With the R92's 20" barrel you should see 2014 FPS at 70° with the chronograph corrected to the muzzle.

[joec]

Hornady shows for H110 the following;

28.2 1400 fps
29.0 1450 fps
29.8 1500 fps
30.6 1550 fps
31.4 1600 fps