A tale of four .308 semi auto rifles (comparison of LaRue, S&W, and Colt .308 AR pattern rifles)

  This is a guest post written by a friend in the firearms industry who likes to share his knowledge and findings but doesn't have the time publicize them as much as they merit.  Said friend is a former Marine Scout Sniper who prefers to post real world, not cherry picked groups. 

Near to far: Colt, S&W, LaRue PredAR and OBR

 

Today I just wanted to get some rounds through the two new rifles and see how well a LaRue mount would work being swapped between the four rifles. Scope is a prototype 3-17x w/ 37mm objective vs the 44mm(normal).

Basic drill was to mount the scope, shoot at a rock on the berm at about 190, adjust POI so it was a bit low, shoot correction at berm and if good shoot one round on paper at 100yds do a final adjustment if needed to get the POI close to POA and confirm.

First rifle was the Colt, had a failure to feed on the first round, cleared it and took a few shots w/ adjustments on the berm then shot at the little black silhouette in the center of the tgt. Did a final adjustment and shot another round. Recorded the dope for that rifle, rezored the turrets on the scope and moved the scope to the next rifle. Did that for all four rifles so each had a POI within about one inch of the POA.

The ammo was Hornady Steel Case 155gr, not the best for precision but good enough for today..in the past it has shown it will hold at about 1" for the OBR and about 1.5" for the PredAR.

After the hasty zero on the four rifles I went back and shot each for a five shot group: mount the scope, redial on the recorded dope, shoot five, zeroed out the turrets and moved the scope to the next rifles etc...After the first series of groups I was not feeling comfortable with how loose the locking levers on the LaRue mount felt on some of the rails so I snugged it down a bit and repeated the exercise(yellow groups). Called it good 'nuff for today.

 

Initial groups at 100yds w/ various ammunition on the S&W. Will repeat them as I'm not into using 'a group' as a benchmark on how well a type/brand of ammunition shoots. Took about 1 minute to shoot each group with 5 minutes between groups to let the barrel cool down some.  Brands of ammo were: Hornady, American Eagle, Remington and Federal.

Groups will be shot in reverse order next time out. 

 

 Shot these in reverse order from yesterday using the S&W.....  Colored holes represent the groups from today, top left group(green) was last and showed me being a bitch and anticipating recoil....threw in a few other bad shots.....

 

Next will be the Colt.

Rough zero with the Hornady Steel Case 155s from previous shooting. Types of ammo used, in order of groups(same as with the S&W):

 

Fired first string starting top left target, about 1-2 minutes between groups. Took 10 and then shot the second string(green circles) starting bottom right:  

Did the the same as with the S&W and 901, five shot groups about 5min between groups. Second string of groups was shot in reverse order

LaRue PredatAR

Same ammo and groups as with the other three rifles....only major difference is that I did not break five minutes between groups, just the time needed to reload a mag with the next five rounds and get back in position to shoot. There was a break in firing while the first string of groups was marked.

LaRue OBR