Allen Mag Shooters Group

[Ridge Runner]

Gentlemen what is the expected barrel life of the 7mmAM vs .338AX for hunting. I could use it until it opened up to 1 MOA or better as most shots would be inside 700 yards. I am guessing the 7mmAM would burn up twice as fast? Are the heavy wildcat 7mm bullets available and how much do they cost?

Wade Carlson

When I first recieved my 7mm AM, I worked up a load with a 160 accubond, its jammed .006 into the lands. Once in a great while due to differences in idividual bullets I would end up with a bullet stuck in the throat while unloading a live round, that was in 2006, now at a round count of approx 460 rds. I've never readjusted my dies and I still occasionaly pull a bullet unloading a live round. never scoped the chamber but I'm thinking throat erosion is very minimal at this point.
Though the 338 will last longer, I'm very happy with my big 7, and satisfied with its longivity considering its intended purpose.

Yes wildcats are available, takes a while to get them, and with S&H I think mine were just over 81 cents each. will try them when the weather breaks.
RR

 

[royinidaho]

Just for comparison.......

I shoot a 270 AM, 30" Lilja 3 groove. Have about 800+ round through it.

Seems to be in about the same shape as Ridgerunner's.

Still 1/4 MOA and 200 and expected increase at beyond 900.

When Kirby gets my new build completed I'll have him bore scope the 270 AM as I'm pretty sure the one I have has been ridden the hardest and put up the wettest of any of them. Should be a good data point.

Me thinks if these extreme cartridges are used as designed any of them will last a couple of life times. Good for the grand kids......

 

[wadedc]

Gentlemen
I just recieved my .338 AM from Kirby and it is beautiful. I am about to start loading ammo and am wondering if any of you have any pointers for loading this caliber? I plan to shoot 141gr H50 BMG with Federal Magnum primer and 300 SMK. I would be interested to hear what OAL you are using as I havent made an OAL gauge yet. I am assuming if it fits in the mag it won't be long enough to cause me any problems.

Wade

 

[Buffalobob]

Kirby can and will tell you the COL based upon the reamer he uses. If for some reason you do not wish to ask him then you should just soft seat bullets and find the lands that way. Record the distance to the lands and COL and you are ready to go. It takes about 30 minutes to get a good number.

 

[wadedc]

I think Kirby must be on holidays as I can't reach him. Do you know anyone who has a .338 AM I could ask advise from? I made my OAL gauge and with the 300 SMK I am 4.190" How far from the lands usually works the best with the SMK?

Wade Carlson

 

[wadedc]

No .338 AM shooter out there?

Wade

 

[royinidaho]

Wade,

I don't shoot a 7mm AM but a 270 AM which should be at least similar to the 7 but probably worse.

I have 850 rounds through it. Had it bore scoped earlier this week. The smith said that "some" though not much cracking. Maybe 50% barrel life left.

If I remember correctly, 1200 rounds was an estimate before the AMs ever hit the street. AMs are supposed to be "huntin'" rifles not plinkers or for those with tinkeritus. Mine has been rode hard and put up wet. Still shots the original accuracy which was a bit better than APS's spec.

Use them they way they were intended by design and several generations can use one.

But........They are very hard "not" to shoot.

 

[cinch]

Yep, Kirby is out of the shop for a bit. I'm sure he will get with you when he gets back.

 

[wadedc]

.338 AM first time out.

I took my new .338 AM to my range for the first time today and WOW nice work Kirby. I don't think I really understood how much energy a 300 SMK at 3400fps had until today! I only loaded a few rounds to see how high I could go before pressure got to high. Took a couple shots to sight in and then the last 2 went under 1" at 425 yards and put about 5/8" holes through my AR400 target. My 338LM barely scratched this same target! Now my only problem is with the scope bottomed out I have to hold 10MOA under the target. Which means 10MOA under plus about 3.75 MOA that the bullet dropped at 425yrds puts me at about 13.75 moa when my scope is zeroed. That is about a 1000yrd zero. Is the only way to remedy this to order a 20 min base instead of my 40 min base?

Wade

 

[royinidaho]

wadec,

This confuses my brain: "Which means 10MOA under plus about 3.75 MOA that the bullet dropped at 425yrds puts me at about 13.75 moa when my scope is zeroed. That is about a 1000yrd zero." Is the only way to remedy this to order a 20 min base instead of my 40 min base?

I can't visualize whether the 3.75 is included in the 10 MOA or added to it as you indicate. I have a tough time getting my head around those kinds of things.

The 20 MOA base isn't the only way to correct this though it would be the better way.

You could do the ol' pop can shim under the front. Kirby would up-chuck his breakfast when he heard about it though.

 

[wadedc]

I am using 10minutes under the target on my reticle and hitting where I am aiming however the bullet drops aprox 3.75 minutes so my actual point of aim is 13.75 minutes. Works fine but if I crank the scope to 42X the target wont even be in the field of view.

Wade

 

[wadedc]

I am attempting to make my range .338 AM proof. Can any of you tell me what ranges these 3/8" steels will stop the 300smk at 3400fps? Ar500, Ar400, mild steel. I have access to all three but it will save me hauling alot of heavey targets around if i can get a starting point.

Wade

 

[bigrich954rr]

GET AR500 it stopped my 270AM at 150 yard with just a small nick in the plate

 

[wadedc]

Have any of you tried the 300 gr berger in a .338 AM. With that BC at 3400fps it should retain alot of energy. Will they hold together on game? I have a bunch of SMK's to use up first but if they are promising I would like to try the Berger some day.

Wade