AWSM Issues

[aishooternz]

Hello All, Sorry for the long winded tale.

recently bought a new AW in 338 from the UK. I cheaped out and bought some once fired brass to get me started and straight away noticed it would not chamber in the rifle ( not too unusual as who knows what the were fired in) After fl sizing i still found some of them either hard to chamber or those that would chamber easily would not catch the extractor and stayed in the chamber when the bolt was opened.

I took the loaded rounds to the range anyway to work up some loads and straight away i was getting sticky bolt lift even at minimum charge weights so i gave up that session and long story short the brass measured .04 too long so i assumed that was my problem and i thrashed myself for rushing to shoot the new gun and not doing my prep.

2nd trip to the range brass trimmed to length easy chambering and there were 2 cases that wouldnt extract (unfired). Virtually all the rounds i had to knock the bolt past the cam to open it. Accuracy was good and apart from the camming of the bolt the rounds didnt show any signs of pressure.. So i gave up again and bought 100rds of Lapua brass which arrived yesterday however i thought i would try and run some of the brass through the gun to see how much better it would be and maybe 90% will not extract.

I am not claiming to be an expert but the only thing i can think is excess headspace causing this, i dont have a no go gauge but did ghetto one up with a new piece of brass and some tape. 6 thicknesses on the bottom of a case and the bolt closed with a little bit of resistance but interestingly the case stayed in the chamber. They fall straight back out when tilt the gun back so i dont think they are getting caught up in the chamber..

I am going to see a local smith that has gauges in the next couple of days but am seeking some advice on other things that may be causing this, and is it something i should be getting AI to fix. I am also getting a decent scratch on the case head from the boltface but i cant see where its bad on fired cases but you can see it on the unfired virgin brass too.

Any help appreciated.

Mike

 

[jeffbird]

Let's start at the start.

Is this a new OEM rifle or used? Does it have the original AI barrel? Does the year code on the barrel match the year code on the receiver?

Buy a box of factory fodder such as ABM, Lapua, or Black Hills. Start with 250 grain bullets. The older AWSM's were not twisted fast enough to run 300's. BTDT. If the factory 250's run fine, which they most likely will, then start with new unfired Lapua brass, run it through a FL die to remove dents and bends in the necks, trim and chamfer. Start off with some 250 gr SMK's, H1000, and F215's, which are very easy to make run well.

Use these to set the FL die to set the fired brass shoulder back 0.0015" - 0.002".


https://www.midwayusa.com/product/47...ith-comparator

Clean the bolt face with Gun Scrubber or brake cleaner. Wipe with a patch with a very light bit oil. Clean the barrel and chamber to make sure there they are clean.

Please post how the factory rounds function.

I had a AWSM and made a mistake selling it. It will get ironed out, suspect ammo is leading the list of most likely issues at the moment.

 

[aishooternz]

Hi, Thanks for replying Jeffbird.

Its OEM rifle with the original slower twist barrel so i will be sticking with the 250gr projectiles.

I have adi 2217 which i think is the same powder maybe and 250gr lapua Lockbase, the few rounds i have shot were pretty accurate with these. Also have some retumbo. Id rather not buy factory ammo as its around $10 a pop here but if you think it might help i could bite the bullet.

I was just playing around and closing the bolt on an unfired new case will not pick up the rounds however if i set the safety to the middle position (firing pin disconnected) i can push the bolt and hear the extractor click and pick up the case i have no idea if thats significant just an observation.

 

[jeffbird]

$10/round! Yikes! I used to joke my Lapua didn't shoot bullets, it shot $5 bills. $10 is a bit strong. Lapua sells 10 round boxes here. Might be worth springing for one box of ten. If it runs fine, then it is an ammo issue. If it has trouble with Lapua factory ammo, then attention is needed elsewhere.

Run that new Lapua brass through the FL sizer. Different brass manufacturers have used slightly different dimensions on the 338 Lapua extractor groove through the years. My AI ran Lapua brass flawlessly. Lapua brass is superb, but can be bent a bit in shipping. Run it through the full length sizer even new out of the box, trim and chamfer. ADI makes H1000, which is AR 2217. It is the go to powder for the 250's. The Lockbases should work nicely.

Go put some rounds through it, especially with fired and resized Lapua brass. It would be very surprising that AI let one out the door incorrectly headspaced.

Good luck!

 

[SurgeonPredator]

The AWM is a great rifle. I love mine.

Did you check the extractor for damage? Does the extractor grab the cases properly on the removed bolt?

Excessive headspace would be an issue with .338, especially since the AWM was not meant for that caliber (modified .300WinMag action). Without a gauge, you can't check properly, but a factory case should still work flawlessly!

I run my AW with 16,2g Lockbase, Lapua case, OAL 91,5mm, Federal 215 primers and 97grs N570 up to 1600m. Without suppressor 913m/s with AI suppressor 923m/s. I had the load checked at our local proof house with 420-425 MPa (so close to CIP maximum).
The .338 might only show overpressure past 500 MPa with Lapua brass, so be careful!

 

[jaycoux]

I have experienced this issue first hand. Buy new brass and your problems will go away.

 

[aishooternz]

Thanks for the replies..

I had the headspace checked yesterday and its all good, however there is still the problem with the brass not being picked up, even the brand new stuff. The guy looked at the extractor and theres no damage anywhere he just thought the extractor may be sitting fractionally lower.

Either way i know the chamber is good now so i will get some more rounds loaded up this week and have another go. Hopefully with nothing to report other than half inch 1000 yard groups

Thanks again

Mike