Black Hills 5.56 77 Gr TMK in Ruger American Gen 2 Predator 223

Joined
Dec 30, 2014
Messages
9,507
guys.. 75 or 77 grain bullets loaded to 2.25” in factory 556 to feed in ARs ain’t going to “jam into the lands” of a 223 chamber.

That said, I did have heavier bolt lift with some 556 ammo in my tikka factory 223 barrel. Nothing big but it was there. I promise the presssures were lower than what is needed to get the velocities touted in Sherman mag cartridges though😂
 

zdc1775

FNG
Joined
Nov 29, 2023
Messages
40
That's great! And I assume all went well? No sticky bolts, bulging primers, etc.?

Yeah, I had no issues with the black hills ammo. I also tested several AAC 5.56 loads and had slightly harder bolt lift on a couple of the rounds but no flattened, flowing, or bulging primers.
 

PsRpOiGrRiAtM

Lil-Rokslider
Joined
Jan 10, 2021
Messages
274
Location
Montana
Just an FYI, but depending on the projectile, you might get jamming into the lands. My Hornady Frontier 5.56 75gr BTHP definitely jams into the lands of my Gen 1 Ruger .223 Predator and sets the bullet back into the case.
 

amassi

WKR
Joined
May 26, 2018
Messages
3,863
Just an FYI, but depending on the projectile, you might get jamming into the lands. My Hornady Frontier 5.56 75gr BTHP definitely jams into the lands of my Gen 1 Ruger .223 Predator and sets the bullet back into the case.

You need to check headspace
Sounds like your about a mile below spec
Luckily you have a barrel nut so easy fix


Sent from my iPhone using Tapatalk
 

PsRpOiGrRiAtM

Lil-Rokslider
Joined
Jan 10, 2021
Messages
274
Location
Montana
You need to check headspace
Sounds like your about a mile below spec
Luckily you have a barrel nut so easy fix


Sent from my iPhone using Tapatalk
I guess I never questioned it. I figured with the difference in throat geometry, coupled with the abrupt "shoulder" on the 75gr BTHP projectile that it was designed for a longer throat and made sense that it would jam.
 

amassi

WKR
Joined
May 26, 2018
Messages
3,863
I don't understand why this isn't the standard cambering for all civilian rifles of the 223/556 variety.

We wouldn’t have fun discussions like this one
It’s a real pain having a chamber shoot bulk 556 and match 223 really well.


Sent from my iPhone using Tapatalk
 

ElPollo

WKR
Joined
Aug 31, 2018
Messages
1,576
I don't understand why this isn't the standard cambering for all civilian rifles of the 223/556 variety.
Because it’s not endorsed by SAAMI or the military. In reality though there’s a huge overlap between all of these chambering. The case dimensions are the same for all of them. The difference is the throat. You can find 223 chambers with freebores as long as 5.56. It’s never a bad thing to check to make sure you don’t have a short throat. Once you’ve done that, shoot what you want and don’t worry.
 

ElPollo

WKR
Joined
Aug 31, 2018
Messages
1,576
Just an FYI, but depending on the projectile, you might get jamming into the lands. My Hornady Frontier 5.56 75gr BTHP definitely jams into the lands of my Gen 1 Ruger .223 Predator and sets the bullet back into the case.
The Frontier 75 gr is pretty hot stuff. I’ve had stiffer bolt lift with it in my Tikka, but not hitting the lands. Tikkas tend to have longer throats.
 
Joined
Dec 30, 2014
Messages
9,507
Because it’s not endorsed by SAAMI or the military. In reality though there’s a huge overlap between all of these chambering. The case dimensions are the same for all of them. The difference is the throat. You can find 223 chambers with freebores as long as 5.56. It’s never a bad thing to check to make sure you don’t have a short throat. Once you’ve done that, shoot what you want and don’t worry.

I've seen reamer spec tables showing slight body dimensional differences as well, more specifically the wylde is looser than the 223 and 556.

I don't think most tikkas have long throats in 223s either. Not like you can seat the heavy bullets out far without jamming.

I may have misspoke earlier if folks are having 75 BTHP jam the lands at AR mag length in 223 chambers.. That still seems like something that shouldn't be a thing on properly chambered rifles?
 
Top