Lightweight 300BLK Bolt Action, help me build it

man32ahan

Supporter
Supporter
Full Member
Minuteman
Feb 2, 2018
691
152
34
Fairfield, Illinois
Illinois passed a rifle law for deer hunting limiting to certain calibers. I was using a pork sword pistol with brace, but that option is gone now. Wanting to build a bolt action 300 blackout as I have lots of 300 BLk Barnes ammo and the recoil is minimal for the kids and wife. Here’s what I’ve got so far:

Action: Origin Action
Barrel: Proof Carbon Fiber
Stock: MDT HNT26

Would you do anything differently for lightweight and accuracy?

It also has to be left handed so that limits my options especially on just buying a factory 300 blackout bolt action rifle (I don’t like factory rifles anyways I’m a snob).

What gunsmith would you use to spin up a 300 blackout barrel on the action?

Thanks in advance.
 
  • Like
Reactions: powdahound76
@Rthur
Can you help this guy out with a 30 LOL?

L-R:
30 BR 1.500" (Normal case length)
30 LOL 1.400" (30 BR cut to 1.4)
30 Dasher 1.400"
All loaded with a 125 Nosler BT.

2900fps with a 22" barrel.
Not sure what the stubby Dasher will do.

20230102_174736.jpg


Thought I'd throw that option out there for you.
 
I have a steel 3b 1/8 barrel I am gonna get fit for my Origin

Im gonna have Fritz at Black Canyon Customs do mine.
He is local to me and his work is worth mailing stuff IMO.
Great guy too.

Im not sure why so light for ILL whitetail hunts?
Lotta $ in that chassis.

Something light with an AR buttstock would make it more adjustable for the kids.

Im using a Luth AR MBA4 on a light chassis for my daughter.
Grows with her and can fit me easy (she isnt quite ready for load development, so thats my job)
 
What restrictions do you have to work within? I’ve killed a few with my blackout and results have been less than impressive. Never lost one, but terminal effects were poor. Two didn’t exit, one of which was a target bullet that pretty much looked the same, would have thought it would pencil through. Almost no blood trails. They were all shot in Louisiana woods at less than 100yds, absolute perfect shot placement was the only saving grace.
 
Yes. Definitely. Probably want to limit shots to 250yds or so. I load Barnes 110gr TAC TX with 20.5gr H110 and get 2450 - 2500fps out of a 14.5" AR. That will definitely get it done on whitetail. If you want to get fancy look at the 300 Hamr from Wilson Combat. It's just a slightly longer 300BO. You can probably get another grain of powder in it and in a bolt action you won't be limited to pressures like in an AR. Maybe looking at 2600 pushing a 110gr.
Same here....110 Barnes 20.1 H110 is 2250fps in 10.5", 2450-2500fps in 16" and does the job nicely.

I am currently on the 300 Hamr road myself and have been pretty frustrated. Working directly with Wilson Combat CS/Gunsmith now to determine what's going on. Its been a very inconsistent cartridge for me to say the least. Not quite what the internet says about it but that is my experience.
 
Yeah, I've noticed everyone who posts velocities are reporting 300BO speeds vs the Wilson advertised enhanced speeds. I figure if you're going to make it work, it would be in a BA where you're gun would be much more tolerant of pressures. When I researched the HAMR Wilson's article made it sound like it struggled as a cartridge until he used CFE Black. Like it was a one powder cartridge.
I cannot get consistent accuracy out of 300Hamr. Tried everything I know to do that works with other calibers. 3/4" groups turn into 3.5" groups with no explanation in 3 different barrels. 135FTX and CFE black are a consistent 1-1.5" but only 120-150fps faster than blackout and then is a one trick pony.

Ive about decided to ditch it and get into 458 socom. After finishing my 11" pin and weld RARR 300BLK build.
 
  • Like
Reactions: reubenski
@Rthur
Can you help this guy out with a 30 LOL?

L-R:
30 BR 1.500" (Normal case length)
30 LOL 1.400" (30 BR cut to 1.4)
30 Dasher 1.400"
All loaded with a 125 Nosler BT.

2900fps with a 22" barrel.
Not sure what the stubby Dasher will do.

View attachment 8212112

Thought I'd throw that option out there for you.
I built a 30 RAR, more case capacity. 500 dia case of the trimed 450 bushmaster brass, feeds well with 450 bushmaster mags in an AR 15..
Would be even better in a short bolt action, uses a 308 bolt, with a .500" dia body & SR primers potential for excellent accuracy like a 30 BR with more capacity. Pictured: 30 RAR, 6 mm ARC, 6mm Dasher for size comparison.
 

Attachments

  • 20230923_011637.jpg
    20230923_011637.jpg
    514.6 KB · Views: 46