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45 raptor, a new AR10 caliber

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45 raptor, a new AR10 caliber was created by foxhunter

see below. pictures of the new round and ballistic data comparing it to AR15 large calibers are included in that article in the Firearm Blog.

Personally, I am trying to figure out what this round would be useful for in North America that a 308 round wouldn't already do. I suppose in short range hunting in thick brush it could be useful.

"Master cartridge designer Arne Brennan, the original inventor of the concept that became the 6.5mm Grendel, has developed a new round for the AR-10 platform. The 45 RAPTOR case is a necked up .308 Winchester case with a case length and body dimensions of a .460 S&W. It packs a much greater punch (30+% more energy at 100 yards) than AR-15 big bore cartridges such as .50 Beowulf, .450 Bushmaster or .458 SOCOM.



The cartridge has been designed for hunting medium and large North American game with a semi-automatic rifle and a barrel 16″ long (or longer). Because it is based on the .308 Winchester case, the only modifications to a standard AR-10 is a .45 RAPTOR barrel, a special barrel extension and modified magazines. No other modifications need to be made, saving shooters money. .45 RAPTOR cases can be reloaded with .460 S&W dies and a .308 Win. shell holder. .460 S&W dies are standard products (ie. non-custom) and manufactured by Hornady, RCBS, Redding, Lee and Lyman. The .45 RAPTOR uses .460 S&W reloading data, which is published by Hodgdon, Accurate Powder and Alliant Powder."
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9 years 11 months ago #38391

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Replied by SOC on topic 45 raptor, a new AR10 caliber

Bear, buffalo, hogs, moose, brush where you don't want twig, bush, leaf between the bullet and vitals to have an effect on flight path.

Looks like a nice alternative to having a bolt opened up for 450 Marlin.


I'm tinkering with taking a 408 chey case, turning the rim on a lathe down to 308 rim size, shorten and stuff .510 bullets into it.

Turns a 308 mag into a single stack...
9 years 11 months ago #38398

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Replied by MrMarty51 on topic 45 raptor, a new AR10 caliber

HA, I found some more information on this round.
www.45raptor.com/45RAPTOR/resources/
Things is moving fast now.
What`ll You say when Jesus asks, Why did`nt You read My book ???
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9 years 11 months ago #38401

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Replied by NightForce on topic 45 raptor, a new AR10 caliber

It's a different round entirely. Although very few items are required to change a complete upper minus the bolt carrier assembly would make for a minute or less changeover... :thumbs:
9 years 11 months ago #38410

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Replied by Libertarian623 on topic 45 raptor, a new AR10 caliber

Soc - I like the idea of making a ar10 a single stack . Have you given a thought as to the ballistics of the proposed round, that was a rhetorical question wasn't it. So what did you come up with. I have to believe your going to come in just short of the 300 Hulk. And given the volume of the 408, the majority of R&D will be trying to contain that pressure.
Last edit: 9 years 11 months ago by Libertarian623.
9 years 11 months ago #38419

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Replied by SOC on topic 45 raptor, a new AR10 caliber


Case capacity looks to be more than the 300 Win Mag but less than 338 Lapua.

However the case is capable of handling higher pressure. The 338 Lapua maxes at 61,000 Psi the 408 at nearly 64,000.

I have two primary R & D branches for this round as I have almost nixed the idea of using a 338 cal bullet in it.

1. .510 AKT

I'm looking at a mold that casts a 950gn .510 gas checked bullet ment for sub sonic 50 BMG. I think the case would push this bullet just over sonic if maxed out even in a 16" barrel.

2. 300 AKT

I have been VERY impressed with other peoples results in loading the new 230gn Berger in 300 win mag, 300 Rum, and 300 wsm. I have them on order for my 300 RSAUM.

With a Muzzle velocity of 2700fps and a my local altitude of 3200ft the bullet is supersonic to 2750yds (1 mile)

This is a better BC than I have seen from any 338 Lapua load.

The 300 AKT should push it over 3000 fps using short mag powder.



There is enough steel in the chamber wall to max the case pressures.

To convert any 308 AR-10 to 300 AKT you would just need to send the barrel to me, I ream it to 300 AKT.

I would recommend the heaviest buffer you can find, an extra power buffer spring and an adjustable gas block.

I wont know if those are going to become required until I do live testing.
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9 years 11 months ago #38468

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Replied by Libertarian623 on topic 45 raptor, a new AR10 caliber

SOC- First I am glad your on our side. That said I am totally in on this project, you say when and I will send a barrel. The 300 AKT sounds like just the thing for me. I don't know who wouldn't want one. Will defiantly need a brake on this baby. Send me a PM about specifics, as to what you require.
9 years 11 months ago #38474

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Replied by OleCowboy on topic 45 raptor, a new AR10 caliber

As always, SOC has got it going on :twothumbs: :twothumbs:
9 years 11 months ago #38540

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