375/08 vs 375 raptor

[Wolf76]

I'm a bit late to the conversation, but have you considered a 45 raptor?
I know for certain it smacks stuff real hard.

 

[marksman1941]

I'm a bit late to the conversation, but have you considered a 45 raptor?
I know for certain it smacks stuff real hard.

I looked hard at the 45 raptor, but the little information I found on it seemed to indicate that feeding from a bolt rifle was inconsistent at times. I don't know why, really, but I ended up deciding on the 375 route as that seemed to be more favored. Theres so little info out there on any of it it's hard to know for certain really.

 

[marksman1941]

I have both Lee and CH4D dies.

The lee die doesn't seem to form the shoulder back far enough when I check it with my case gauge. Like maybe 1 or 2 thousandth short. This could be tolerance stacking or something. I need to try a different shell holder.

Anyway, my main die is the CH4D.

Lightly lube 358 case with imperial sizing wax. Run through the 375 Raptor FL die once, then clean off lube. (So one step from 358 to 375)

Check headspace with case gauge (usually perfect with the CH4D die).

Then trim til perfect according to case gauge.

I have heard of guys going from 308 straight to 375, but I assume that was new brass. Once-fired brass might be harder and prone to cracks.

When I was buying dies, I bought a Lee 375 raptor die before realizing I needed the 375/08 die. When I spoke with ch4d and got their 375/08 die, he mentioned that the Lee Raptor die had a rep for being out of spec in some capacities and a lot of folks had trouble with them.

Ch4d convinced me I needed a middle step between 358 and 375, but I haven't used them yet to know if it's actually needed. I don't have imperial sizing wax on hand though, so I'm glad you mentioned that. I'll order some up.

 

[ShadowAviator]

When I was buying dies, I bought a Lee 375 raptor die before realizing I needed the 375/08 die. When I spoke with ch4d and got their 375/08 die, he mentioned that the Lee Raptor die had a rep for being out of spec in some capacities and a lot of folks had trouble with them.

Ch4d convinced me I needed a middle step between 358 and 375, but I haven't used them yet to know if it's actually needed. I don't have imperial sizing wax on hand though, so I'm glad you mentioned that. I'll order some up.

I was playing around with the dies. And I think the issue with the lee die was tolerance stacking and some user error.

Of my two shellholders there is a .001 difference.

I also screwed the die in bit to make sure I was getting enough force when it would cam over.

Messing around with that seems to have fixed the issue with the lee die.

I am a new reloader, so I am still figuring things out a bit.

On the sizing steps, are you sure he said 358 and not 338?

The expander dies he recommended to me (which I bought) go from 30-35 and 33-38. One die necks up to 35 cal and the other die would neck it up the rest of the way to 380. The FL die would bring it back to 375.

 

[marksman1941]

I was playing around with the dies. And I think the issue with the lee die was tolerance stacking and some user error.

Of my two shellholders there is a .001 difference.

I also screwed the die in bit to make sure I was getting enough force when it would cam over.

Messing around with that seems to have fixed the issue with the lee die.

I am a new reloader, so I am still figuring things out a bit.

On the sizing steps, are you sure he said 358 and not 338?

The expander dies he recommended to me (which I bought) go from 30-35 and 33-38. One die necks up to 35 cal and the other die would neck it up the rest of the way to 380. The FL die would bring it back to 375.

Looking at my die set, they gave me a fl sizer, a seater, and a 32-37 expander die which he suggested be used for 358 win

 

[ShadowAviator]

That sounds fine to me. Those guys would know way more than I would. I was trying out the expander this morning and it's alot smoother and gentler than just using the FL die on the 358 brass.

I think I will change my steps to first go through the expander die then into the FL die. It's smoother and probably saves wear on the FL die.

I guess there are probably ten different ways to form brass.

Hopefully, I won't have to convert much brass. I'm not sure when the raptor brass will be available, but it sounds like it will happen.

 

[marksman1941]

That sounds fine to me. Those guys would know way more than I would. I was trying out the expander this morning and it's alot smoother and gentler than just using the FL die on the 358 brass.

I think I will change my steps to first go through the expander die then into the FL die. It's smoother and probably saves wear on the FL die.

I guess there are probably ten different ways to form brass.

Hopefully, I won't have to convert much brass. I'm not sure when the raptor brass will be available, but it sounds like it will happen.

I think the smaller steps a person takes, the less stress the brass will be under and the less chance of cracking/thin spots to occur. If you've got the die, may as well use it. Especially since that's just a one time action. Once you've converted a couple hundred cases you're most likely set for a good long while, depending on your intended use.

 

[maaorava]

Been dealing for a while with 375 raptor AR-10, no idea of reamer maker, but when got the gun, went back to gunsmith, needed to add freebore, it was way too short. He just used some 375 neck reamer when I waited and we tested the gun at his backyard to adjust allso the gasblock, was easy fix. Have CH4Dies. Forming from 308 to 375 raptor is easy if brass is soft, have used Sako and Lapua cases, almost 100% success with CH4Dies FL die. I annealed the cases (oncer shot as 308 factory loads before formed to 375) after first shot as 375, and looks like the steeper shoulder angle of Raptor compared to 308 has formed correctly when firing first time as 375 Raptor. If someone uses not so soft brass as Sako and Lapua's necks are, annealing may be a good idea before forming if someone uses once fired brass. The shoulder angle is so steep, same phenomen as forming 300 AAC BLK from 223 cases. Sako/Lapua neck thickness is too thin to get enough neck tension in my AR-10. Jacketed bullets or copperplated CamPro 250 grainers are OK, but many solid copper or brass solids need more tension, maybe due too small neck thickness of from 308 to 375 stretched Lapua/Sako necks and formed with CH4Dies dies. Solution? Just cheap Lee 375 H&H factory crimp die, and cut the die body and inside moving part to become a bit shorter in order to crimp 375 Raptor cases. Just use some time to measure and study the die function and calculate needed dimensions. Voila, short Raptor neck with under sized boreriders not anymore a neck tension problem in a gas gun.

 

[Alibiiv]

I had heard that 358 was the easiest to convert. And probably smart so that it has its own head stamp (since I don't own a 358). I hadn't heard about using 300 savage brass though. I'll have to look into that

I have been making .375 Raptor brass out of Federal .308 match brass. It is once-fired stuff, annealed and cleaned. I use Sinclair mandrel dies and Hornady One Shot. So...one shot with the .356 mandrel and one shot with the .373 mandrel and done. No issues whatsoever.

 

[Alibiiv]

Presently I have a Ruger 77 at the gunsmith getting ready to have it rebarreled and rechambered to .375 Raptor. After reading this thread it has me thinking that the .375-08 might be a better choice due to the extra length of the neck. At this time in the build it is time to reconsider what to chamber this build in?? Has anyone had any experience with either cartridge?

 

[marksman1941]

I ended up deciding on the 375/08, although I haven't bored my rifle out yet for it. It made sense to me to go that route due to the longer neck, although if a person were to want an ar15 in 375 raptor as well then I would stick with the one caliber.

If you need dies for 375/08 or bullets, let me know and I can help you out.

 

[Alibiiv]

I ended up deciding on the 375/08, although I haven't bored my rifle out yet for it. It made sense to me to go that route due to the longer neck, although if a person were to want an ar15 in 375 raptor as well then I would stick with the one caliber.

If you need dies for 375/08 or bullets, let me know and I can help you out.

Okay great. I have .375 Raptor dies, my son built a Raptor on an AR platform using an X Caliber barrel. The first time out, the rifle really didn't shoot well at all. I am hoping that it was the plated, 250gr bullets that we used an not the rifle itself. His AR is put together with top shelf parts, it is not junk at all. If I decide to go with the .378/08 the smith that is doing my work ought to be capable of rechambering his barrel while he is at it. Thanks for getting back to me on this. The .375/08 makes a whole lot more sense to me than trimming back the necks on this brass and only shortening the brass by .150 thousandths.

 

[marksman1941]

I don't know if the 375/08 has any issues in an auto. I can't see the nominal COAL difference being a problem, but you might look into that and see if it would make feeding an issue to be a hair longer.

 

[Wild Monkey]

My experience has been these larger Caliber Wildcats like the .338-06 for instance, the .308 Caliber actually outperforms the larger Caliber bullet downrange. Unless of course you are seeking a subsonic Rifle.