FNG building first AR-10A

[AngelDeVille]

Ar-10 is done, and so is the ar15 pistol.

[unforgiven]

Nice job brother,I like the para cord setup. <thumbsup>

[AngelDeVille]

I just gotta be different.

[AngelDeVille]

I have fired in excess of 400 rounds of ZQI and 147 gr reloads in the past few weeks, so the rifle shoots very well. I adjusted the gas block so the ZQI ammo functions well, as it seemed to be the lowest power of what I was shooting.

 

 

So Sunday I finally got to the range to test out my Bulgarian 180gr bullets and re-used mil powder. ( I also got to shoot my .300 BLK)

 

I had decided by case volume, and crono results with the original ammo out of a Fin M39 that 42-44 grains of powder in 1/2 grain increments was well within safe limits for this powder. I load up 10 each.

 

I didn't bring my crono....

 

SO......  I add two rounds of the 42 grain to my magazine, fire one. inspect the case, doesn't look too unusual. #34 primer doesn't look excessively flat.

 

The second round does not strip from the mag, so I figure it may be low powered. I load the second and fire. 100yds, both bullet holes touching.

 

Recoil seems normal.

 

I move to two rounds of 42.5gr, AGAIN problem stripping round #2, I lose a primer upon extraction on one of the rounds, I attribute this to loose primer pockets. Other primer looks ok.

 

I go back and load two more 42 grainers, fire one, and again problem stripping the next round, this time the #34 primer has flattened and evulsed into the firing pin hole in the bolt.

 

Then it clicks that the stripping of the second round from the mag is due to the bolt traveling TOO fast.

 

SO I pack up the 45 remaining rounds and pull the bullets and dump the powder.

 

So the case splits in the original ammo was the result of excessively hot ammo loaded by prison labor.... go figure....

 

I get home and open another tin of the 7.62x54r ammo and the average powder charge is 49 grains, VS the 51 grains in the last two tins!

 

Back to the drawing board!   My next batch for my .308 will be from 38-40gr in 1/2gr increments, I'll be bringing my crono and looking for an accurate load in the 2550-2600fps range.

 

 

Good thing I didn't start with the 44grers......