Bump this up tommorrow in the 8 am to 8 pm to get reloader(s) replies....

 

Short answer ...
YPMMV!

Long detailed technical answer,
It is not so much the chamber pressure that is the issue, it is the residual pressure at the gas port that may be critical. Some of the newer high performance .308 WIN ammo maintain a sensible SAMMI spec chamber pressure, but are designed more for BOLT action rifles, so the residual pressure way up the barrel at the gas port may vary considerably from the 7.62 NATO spec the M14 was originally designed around. Slower powders, powder with a retardant added, or "Duplex" powder loads all increase velocity by maintaining burn for longer duration.

The gas assembly on the M14 is somewhat forgiving of slight port pressure increase, but if you want to play with the bleeding edge of power and velocity in an M14, then get yourself a grooved piston or an adjustable/ ported gas plug.

The long distance/1000 yd/ match M14 shooters will probably have more experience with this issue. They are always pushing the envelope. Hopefully some of them will chime in here with more specific answers.

PS: I have been shooting some of the higher velocity NOSLER 168 gr HPBT Match loads in my bolt rifle, my AR 10, and my M14. This ammo is labeled as having a muzzle velocity 100 fps faster than 168 gr Federal GMM. All three of these rifles have VERY tight .308 Win chambers. The Nosler ammo is superbly accurate in my bolt rifle [ one ragged hole for 4 shots ], does about 2" in my M14 [ still dialing the M14 in ], and sub-moa in my AR 10.

BUT,
the AR 10 has a carbine length gas system, and was way over gassed with the Nosler ammo. Cratered primers, and a couple of loose primers were the warning signs. The M14 gas system with the op rod is a lot more complicated and generally considered more fragile than the AR direct impingement gas system. But in this case, with the shorted carbine gas system port location, the AR 10 was scary, and the M14 was not.

as I said,
YPMMV!

 

Short answer ...
YPMMV!

YPMMV!

I dont understand HA

 

What's the purpose of the round? Hunting, paper punching, 1,000yds? I can't see a use for a 150gr bullet to travel that fast. If you're going to shoot 1,000 yards, I recommend a 175 grain bullet flying at least 2600fps. It will buck the wind better. M80 normally clocks in at around 2800fps.

168 grain hybrids can be pushed pretty hard for 1,000 as well but if you keep any 168 at 2650 fps, you won't overwork the rifle and that will get you to out to 600, easily. I think Nez runs his 168's to 2800, but that's pretty hard for an M14.

If you're looking for hunting, a standard velocity 150 grain bullet will do fine out to 300 yards and maybe more. I personally use 165's for hunting.

Tony.

 

What's the purpose of the round?

I personally use 165's for hunting.

Tony.

Im trying to find a bullet my gun likes. That is also carried by my local gun shop. My gun shoots 168gr SMK very well but i have to order them.

My gun also likes 165gr hornady. I just wanted to try 150gr to see if she likes it. But then i noticed the FPS.

Thanks all.

 

My experience with Hornady Superformance ammo is that they tend to Hot Rod it from the factory. I often buy it in 6.5 x 55 Swede and 243 Win. just so I can punch paper with it, and reload the brass! I'm a Hornady Brass hound when it comes to the aforementioned calibers.

With that being said, I would think a lot of it might depend on your specific rifle and barrel. My new production SAI Loaded is chambered in 308 Win, so it should be able to handle any factory ammo. Hornady takes these things into consideration and does extensive testing on their load development before it goes into production.

I know this isn't the answer you are looking for, but it's my 2 cents.

 

If you hand load, that's a different subject entirely. If you have to buy ammo that is factory made, look at the American Eagle 168gr OTM. It's extremely accurate and usually cheaper than the Federal Gold Medal Match. I've had good luck with Nosler 168gr match ammo too.

Are you a hand loader?

From SAI's M1A user manual, page 4...
http://www.springfield-armory.com/wp-content/uploads/2014/03/M1AManual.pdf
Ammunition recommendations for your M1A rifle: use commercially produced, new .308 caliber full metal jacket, hollow point or ballistic tip type of bullet. Do not use
soft point or “light magnum” type ammo.

150gr ammo loaded to 3,000FPS is considered "light magnum".

Tony.

 

No use in jumping that round up that high. If you are trying to reach out farther, then just use a different projectile. My general rules are :

0 - 600 use 150g
0 - 800 use 168g
0 - 1000 use 175g

For plinking or no accuracy desired shooting I just use whatever is cheapest like ZQ, Tula, Perfecta.

For everything else I use 175g.

 

Pretty much all of my loading for the M14 I like to keep between 2500 and 2750. Lighter stuff, 110 to 125 gr I sometimes kick er up a notch to around 3000 if I am shooting steel at variable range estimates. I worry more about throat erosion than I do op rod damage with hotter loads.
.

 

The Hornady Superformance line is relatively new. They supposedly are using a powder blend that increases velocity without increasing chamber or muzzle pressure.

I would ask them directly about the port pressure in an M14 platform. They are advertising Superformance Match ammunition, so they may have tested already tested it.

 

Is 3000 FPS to much? Unless you have access to a powder with special burn characteristics, or unless you have a tunable gas plug to moderate the port pressure; yes.

Hornady superformance 150gr SST I shoot 155 Scenars at 2950 fps--in a BOLT gun. I shoot the 155s at 2700 in the M14.

Will i harm my op rod? Probably Is chamber presser to high? maybe maybe not--its the port pressure that eats the gun alive.

 

No i am not reloading yet.

I think ill just save this ammo for my bolt gun. My M14 shoots sub 2 MOA with it. Not better than SMK

Thanks for all the help guys. I learn everytime i post a thread.

 

3000 fps way too fast as above for distance heavy bullet and slower speeds.

 

I've gotten to 2950fps with a 155 on a hot day, and it wasn't pretty. Gas blowing around the edges of the primers. And it felt violent. That was with surplus 4895. 3000fps strikes me as marginal at best, and might lead to immediate troubles on a hot day.

I wouldn't shoot them often if at all. Besides the oprod, I think you run the risk of cracking the receiver heel.


The Superperformance line replaced the LightMagnum line which was a known no-no in gas guns.