Improving the 308 Win performance

[JAYgs8163]

Can't go wrong with a 14, no drama like what you read associated with the large frame ARs. At one time I built a dozen of each. Been selling them off, down to 4 each now. If I were to keep only one it would be this particular one. Have enough GI spare parts if I were to need any.

There is some aura in a rugged battle rifle.

If you were anywhere serious about a 14 for a truck gun, start looking around for Navy SSR scope mount. Some pictures on this article.

Replica Navy M14 Sniper Security Rifle (SSR) completed

Just received from the builder my replica of a US Navy M14 Sniper Security Rifle (SSR). It’s not exactly a ‘vintage’ sniper rifle, as they were in service circa 1996 to around 2011, but it was the last of the Navy M14 sniper rifles, and I thought others might find this project interesting. No...

www.snipershide.com

Over the years I tried every mount option out there, none compared with the SSR mount. Here is a close up of mine. I have since added a blank firing device shield to mitigate the blowback when shooting with a can. Modified the gas system as well.
View attachment 475667

Excuse my ignorance but this rifle is a 308 with a 22" barrel?

 

[bamban]

Excuse my ignorance but this rifle is a 308 with a 22" barrel?

Correct, 308Win, 22 inches, standard barrel configuration for the 14

 

[nralifer]

Why did you have to say that? Now I need to go buy another couple pounds. Haha.

That's life. As Forrest Gump said: "Life is like a box of chocolates. You never know what you sre going to get."

 

[USAFRet]

That's life. As Forrest Gump said: "Life is like a box of chocolates. You never know what you sre going to get."

Accuracy, sir. That is what I seek. I will taste as many of the chocolates I can and give Jenny back the rest. She is the most evil person ever in a movie script, anyway.

 

[USAFRet]

Excuse my ignorance but this rifle is a 308 with a 22" barrel?

Mine would have the barrel cut down to about 18" with a shortened LOP.

 

[nralifer]

@nralifer Yes, all the same POA. I missed the 2nd part, so here. Top to bottom taken through the spotter. 47 grains first. The shot way out was the shot was boresighting shot from another rifle. 49.5 went back right with the other. 49, and 48.5 are out of the black. The 49.0 barely shows at about 11 on the white.

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I didn't originally planned on showing these, as it is just a short ladder per se. I planned to do load work at 500 on eTarget

The next step would do is a jump ladder with 2 shots at each increment of jump and pick the jump that groups the best.

 

[bamban]

The next step would do is a jump ladder with 2 shots at each increment of jump and pick the jump that groups the best.

My question to you still stands. What is your solid grouping with the 150s? COL, neck tension? Fireformed brass or virgin?

 

[nralifer]

My question to you still stands. What is your solid grouping with the 150s? COL, neck tension? Fireformed brass or virgin?

From a bolt gun and 20" barrel I get 1/2MOA accuracy with once fired Lapua Palma brass. Neck tension is about 0.002". CCI 450 primers or Remington SRP primers. Use either Savage short action or American rifle Company Nucleus action with barrel nut.

 

[nralifer]

My question to you still stands. What is your solid grouping with the 150s? COL, neck tension? Fireformed brass or virgin?

Reviewing my first snswer to your question above I failed to mention that I have two different chamber designs that differ in the length of the free bore. The one I am using currently has a shorter free bore such that the COAL of the round is 2.915" for a 0.025" jump. My other barrels have a longer free bore an will accept a 2.980" COAL that is still magazine friendly.

 

[bamban]

Reviewing my first snswer to your question above I failed to mention that I have two different chamber designs that differ in the length of the free bore. The one I am using currently has a shorter free bore such that the COAL of the round is 2.915" for a 0.025" jump. My other barrels have a longer free bore an will accept a 2.980" COAL that is still magazine friendly.

Thanks..

We're close to the 168 Hybrids in COAL, I am running 2.93 single loading the M1a for long range matches. I will concentrate on that COAL as well as 2.83 mag length. Plus, I will switch to CCI41. Due to the nature of the pin hole opening on this bolt, primer flow will show even shooting M118 LRs.

Compared to the 41s, the 205MAR, though developed for the gas guns, tell tale signs the former shows to have tougher cups, maybe thicker. They are the ones I used running 50 grains of 2000MR on my long range double lugs launching the 168 Hybrids at 2800.

The 150 BD2s running 200 fps faster than the 168 Hybrids, both at advertised at similar BCs, I will definitely run the 150s next time we go after some hogs at a friend's family spread. From the ranch house back patio there is a 400 yard feeder where I shoot hogs with 300WM. It will be a good test on these 150s how they perform on hogs.

It will be a couple more weeks before I head back out to do load work, will keep you posted.

 

[nralifer]

Thanks..

We're close to the 168 Hybrids in COAL, I am running 2.93 single loading the M1a for long range matches. I will concentrate on that COAL as well as 2.83 mag length. Plus, I will switch to CCI41. Due to the nature of the pin hole opening on this bolt, primer flow will show even shooting M118 LRs.

Compared to the 41s, the 205MAR, though developed for the gas guns, tell tale signs the former shows to have tougher cups, maybe thicker. They are the ones I used running 50 grains of 2000MR on my long range double lugs launching the 168 Hybrids at 2800.

The 150 BD2s running 200 fps faster than the 168 Hybrids, both at advertised at similar BCs, I will definitely run the 150s next time we go after some hogs at a friend's family spread. From the ranch house back patio there is a 400 yard feeder where I shoot hogs with 300WM. It will be a good test on these 150s how they perform on hogs.

It will be a couple more weeks before I head back out to load work, will keep you posted.

 

[nralifer]

That's great news. You opened up the use of the 150 BD2 in the M1A platform and demonstrated it's equivalency to a bolt gun. PM me some time. I would like to discuss something with you. It is all good.

 

[Litrfoot]

I have been using for years the 150 BD and BD2 bullets with MVs of 2920 from a 20"barrel and 3050 from a 24" barrel using Leverevolution which outperforms most 3006 loads. Have killed African Plains Game and a large Alaskan Coastal Black Bear all with single shot DRT kills. The attachment is a JBM trajectory calculation of our 175 gr BD2 bullet propelled from a 24" barrel which I think is entirely achievable for the 308 Win at 4500 ft elevation, which is not an unusual elevation to hunt Elk. The higher you go the better. At 900 yds that bullet still has 1300 ft# of energy snd is traveling at 1836 fps which is at least 100 fps more than is required to get it to expand. What makes this possible, and it is the point of the thread, is using a bullet with a high enough BC that will expand reliably at 1700 fps impact. That has already been done by a friend of mine using our 195 gr bullet with a higher BC from a 300WM at 1225 yds.

So in your JBM work up, you're saying out of a 24" 308 Win, with a 175gr bullet, you are running it at 2900fps???? At what pressure, 80000 psi?

 

[Shubey]

This thread would be dedicated to ways to improve the performance of the 308 Win or the 7.62x51 mm cartridge without wildcatting the case. Experienced and innovative reloaders should find this interesting and are encouraged to participate. The 308Win is so versatile, inherently accurate and commonly used, and yet its performance in terms of MV, trajectory and speed is a bit mediocre. I am sure it can out perform the 3006. To start with I offer up my favorite hunting load I have used for the past 6/7 years in the 308Win. The 150 gr BD or BD2 with 49 gr of Leverevolution going 2920 fps from a 1:10, 20"Douglas barrel in a short action rifle. The same load from a 24" Bartlein 1:9 twist barrel goes 3050 fps. This load would be a pretty decent long range Elk load to 900 yds or so.

For Deer...step down to Sierra 125 grain Game Changer Bullet. Plenty of bullet, less recoil,more velocity! I use TAC Powder.