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Discussion Starter · #1 ·
Just curious if any one has done one? Did a search for it and found a post from 07 where someone was selling a factory 7mm08 Springfield m1a but that was it. I'm no expert, but it would seam that it would be relativity easy to convert an m1a by swapping the barrel and using a vented gas plug. I would think that for target shooting the faster velocity and higher BC of the 7mm caliber would make sense.... any thoughts?
 

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I had one in 7mm-08 from the factory, 243 as well. They were the two most accurate out of the box M1a's i have ever owned. I don't see why there would be a problem to convert other than the barrel.
 

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Just curious if any one has done one? Did a search for it and found a post from 07 where someone was selling a factory 7mm08 Springfield m1a but that was it. I'm no expert, but it would seam that it would be relativity easy to convert an m1a by swapping the barrel and using a vented gas plug. I would think that for target shooting the faster velocity and higher BC of the 7mm caliber would make sense.... any thoughts?
Your right, pretty easy too do and you still have good barrel life. No need for a vented plug. SAI offered this as a factory option back in the day, however going from .308 to 7mm08 takes you out of the Service Rifle class and rolls you into the Match Rifle class where the bolt gunners rule the roost................

A 171gr Barnes Match Burner has a clamed BC of .645 and the 185 Berger Hybrid's BC of .569 both need seated long too get enough powder under them too get them up too speed. But there performance between the two is measurable, enough difference that you can see it down range.

7mm 08 is what the M14 should have been chambered in from the start.
 

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Discussion Starter · #5 ·
Id would have to see what ammo availability for the 7mm08 is around my neck of the woods as I dont reload yet. But if I get a second m1a or have one built I might deiced to go the 7mm08 route for a long range target m14 clone. I've done a bit of reading and it sounds like you could use a full length sizing die to neck down 308 brass to work with the 7mm08 although you would have to be careful of neck thickness.
 

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I like the 7MM-08 . Nice Round. In the M1A 7.62x51 is the way to go.
Notice the US Military did not think the 7MM-08 was better than the 7.62x51.
Save your money.
 

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I like the 7MM-08 . Nice Round. In the M1A 7.62x51 is the way to go.
Notice the US Military did not think the 7MM-08 was better than the 7.62x51.
Save your money.
Was it that, or was it that the .30 cal bullet was already so widely used in the military? When did the 7.62 become a NATO round?
 

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Id would have to see what ammo availability for the 7mm08 is around my neck of the woods as I dont reload yet. But if I get a second m1a or have one built I might deiced to go the 7mm08 route for a long range target m14 clone. I've done a bit of reading and it sounds like you could use a full length sizing die to neck down 308 brass to work with the 7mm08 although you would have to be careful of neck thickness.
7mm08 brass is more expensive than .308 for some reason, why....... Hunter Silhouette shooters used .308 brass necked down in a 7mm08 die set and lived with short necks, so I think I can do the same as I have a pile of .308 brass.

The case neck for 7mm08 is .315 and the cases that I have necked down both mil-spec and commercial come in at .315 not good, I don't want too neck turn any brass and spend a pile of time at the bench so a custom reamer with a .318 neck and longer Leade so I can seat the long bullets and still have good case capacity is a must.
 

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Was it that, or was it that the .30 cal bullet was already so widely used in the military? When did the 7.62 become a NATO round?
Well the .308 case was developed as a .30 caliber round, and the military adopted it before wildcatters started necking them down to 7mm, in the late '50s-early'60s. Winchester didn't mainstream it and get it SAAMI'd until 1980.

I've thought about selling my .308 bolt gun and getting a 7mm-08, it is a terrific silhouette shooter at 300+
 

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Was it that, or was it that the .30 cal bullet was already so widely used in the military? When did the 7.62 become a NATO round?
I don't know? Maybe!
+++When did the 7.62 become a NATO round?
Back in the 1960s!

After the 9MM and the 7.62 became intrenched as a NATO round there is really no going back.The Die was cast!
They explored many different rounds before than but they settled on these two.
I don't make the rules I only have to live by them as it were!
 
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Your right, pretty easy too do and you still have good barrel life. No need for a vented plug. SAI offered this as a factory option back in the day, however going from .308 to 7mm08 takes you out of the Service Rifle class and rolls you into the Match Rifle class where the bolt gunners rule the roost................

A 171gr Barnes Match Burner has a clamed BC of .645 and the 185 Berger Hybrid's BC of .569 both need seated long too get enough powder under them too get them up too speed. But there performance between the two is measurable, enough difference that you can see it down range.

7mm 08 is what the M14 should have been chambered in from the start.
The 162g AMAX has a b/c of .625.
What's the max coal of the M1A? This is the Achilles's heel of a semi 7-08.
 

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Well the .308 case was developed as a .30 caliber round, and the military adopted it before wildcatters started necking them down to 7mm, in the late '50s-early'60s. Winchester didn't mainstream it and get it SAAMI'd until 1980.

I've thought about selling my .308 bolt gun and getting a 7mm-08, it is a terrific silhouette shooter at 300+
ahhh, its 7mm08 Remington for a reason and not 7mm8 Winchester.... and its cheaper too rebarrel than a new rifle.
 

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Well the .308 case was developed as a .30 caliber round, and the military adopted it before wildcatters started necking them down to 7mm, in the late '50s-early'60s. Winchester didn't mainstream it and get it SAAMI'd until 1980.

I've thought about selling my .308 bolt gun and getting a 7mm-08, it is a terrific silhouette shooter at 300+
I have a semi finished stainless barrel for a FN Mauser action that I'm finishing. I got the reamer from Dave Kiff at PTG. Should be a fun rifle. Nice thing about the Mauser action is it is a long action...can load the rounds as long as needed. I think Dave designed the reamer for VLD's.
 

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The 162g AMAX has a b/c of .625.
What's the max coal of the M1A? This is the Achilles's heel of a semi 7-08.
Both 7.62 and 7mm08 have the same COAL @ 2.80, when loading for Long Range that's all slow fire this fly's out the window. In order too get good case fill with the 185 B you have too seat them out to 2.95 with the 171 BMB its 2.90 this helps too keep the bullets shank out of the shoulder junction.
 
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Unfortunately with a 2.80 oal the 162's are seated too deep and you lose valuable case capacity.
This is a quote from SH. It's regarding an AR10 build but I would imagine the M1A would be similar:

"I got the following load data from the Hodgdon website. It is for 7mm-08 Remington. I copied the load data for 162gr and 160gr bullets using IMR-8208 XBR powder. At first glance the velocities for the 162gr bullet look pretty good but look at the COL; 2.875" All the 162gr loads are for this COL but we know that we are limited to 2.800" COL by the magazine. The closest bullet weight to 162gr listed on the Hodgdon website with a max OAL of 2.800" is 160gr. Its almost 200fps slower in the shorter loading. These are the velocities I think you can expect from the 7mm-08 in the AR-10 platform with the 162gr load. They match pretty well with my results.

162 GR. HDY A-MAX IMR IMR 8208 XBR .284" 2.875" 36.2 2499 41,000 CUP 40.2 2725 50,800 CUP

160 GR. SPR SPBT IMR IMR 8208 XBR .284" 2.800" 35.5 2459 45,400 CUP 37.7 2554 49,900 CUP"
 

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Unfortunately with a 2.80 oal the 162's are seated too deep and you lose valuable case capacity.
This is a quote from SH. It's regarding an AR10 build but I would imagine the M1A would be similar:

"I got the following load data from the Hodgdon website. It is for 7mm-08 Remington. I copied the load data for 162gr and 160gr bullets using IMR-8208 XBR powder. At first glance the velocities for the 162gr bullet look pretty good but look at the COL; 2.875" All the 162gr loads are for this COL but we know that we are limited to 2.800" COL by the magazine. The closest bullet weight to 162gr listed on the Hodgdon website with a max OAL of 2.800" is 160gr. Its almost 200fps slower in the shorter loading. These are the velocities I think you can expect from the 7mm-08 in the AR-10 platform with the 162gr load. They match pretty well with my results.

162 GR. HDY A-MAX IMR IMR 8208 XBR .284" 2.875" 36.2 2499 41,000 CUP 40.2 2725 50,800 CUP

160 GR. SPR SPBT IMR IMR 8208 XBR .284" 2.800" 35.5 2459 45,400 CUP 37.7 2554 49,900 CUP"
Yea that's using XBR powder, what about IMR/H-4064, Varget, IMR-4320, RE-15? For Long Range slow fire you can seat the bullet longer picking up some case capacity, adding more powder for a longer push equals more velocity.
 
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The .308 Winchester was introduced in 1952, two years prior to the NATO adoption of the 7.62×51mm NATO T65. Winchester (a subsidiary of Olin Corporation) branded the cartridge and introduced it to the commercial hunting market as the .308 Winchester.
 
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