• Watch Out for Scammers!

    We've now added a color code for all accounts. Orange accounts are new members, Blue are full members, and Green are Supporters. If you get a message about a sale from an orange account, make sure you pay attention before sending any money!

  • Site updates coming next Wednesday at 8am CT!

    The site will be down for routine maintenance on Wednesday 6/5 starting at 8am CT. If you have any questions, please PM alexj-12!

338 Lapua Nightmares

S

Scorpion King

Sergeant
Full Member
Minuteman
Dec 21, 2012
103
2
43
United States CA
So I did my 3rd custom bolt action build and was feeling really confident. I had used AICS platforms for a 300 Win Mag build and a 308 Winchester build. Both actions I used were Defiance actions. I used the same Jewell Triggers, Bartlein Barrels, atlas bipods, and Badger FTE Brakes. I used the same ammo specs from the Sierra reloading manual for my projectiles. Both guns ran flawlessly and were the object of desire by the Marine Scout Snipers in my last 2 long range and high angle classes.

Enter the start of my Nightmare on Lapua Street. For this build I used a AI AX Chasis, a Defiance Deviant Action, a 1/9 twist Bartlein Barrel, Badger FTE Brake, and a Jewel trigger. The problems started when my Barrel guy was matching up the action and Barrel. When we went to drop the trigger in there was something wrong with the seer so we had strike one. Managed to get everything together and dry firing, it looked like another beautiful build and I couldn't wait to get it out to the range this weekend. I loaded up 60 rounds for load development and was on my way to our secret spot in the Mojave desert with a couple of buddies.

Unpack the rifle, set up steel and paper targets for sighting this amazing thing in, get my mat and spotting equipment set up, and got in the prone to handle business. I start loading my magazines up with the first 5 Lapua rounds. It looked like OJ putting on a pair of Isotoners in a courtroom. I check my specs and my ammo is dead nuts to specs. 3.680. I then measure the length of the AI AX 338 magazine and it measures 3.650. Is this normal? I then try to feed it manually into my Defiance Deviant action and the bolt won't close. When I got home I used a backup set of calipers to remeasure and things checked out.


Is this normal, I hope not because I am kind of pissed.
 
pyrofx said:
First guess is ...... CIP length round . Non CIP magazine.
Chamber cut for non CIP

Greg
Click to expand...

I know my AI 338 CIP mag is longer then my AI 338 mag. I got the longer one so that I could load out my 300 RUM. AI CIP mag will not fit in non CIP AI stock.
 
Looks like I will be calling Mile High on Monday. How do I get the wrong chasis when I call in saying I am building a 338 lapua mag for a defiance action to shoot 300 grain Sierra Match Kings?
 
I shoot a Surgeon PSR mil spec rifle and the COAL is 3.610 measured with a Hornady gauge and a Sierra .300 MK bullet. The AX magazine is longer than the allowable chamber length. Soon as I get back to town, I am going to test some ammo with a COAL of 3.595 using a Sierra .300 bullet. I fired 500 rounds of HSM using a COAL of 3.600 using Rocky Mountain 300 grain bullets. Worked very well in the rifle. I also shot some production Hornady .285 grain ammo that is a little longer and shot ok.
 
If you dont specify CIP length then you probably not gona get it. Just because you run a 338 dose not automatically mean your running CIP length.

If your going to change to CIP length magazines for your 338 you will need

CIP length mags
CIP chassis
You will probably need to modify your Defiance long action to work with the .125ish longer CIP mags. You will need to cut the feed ramp on the action forward to accommodate the longer mags
 
Sonic Crack said:
If you dont specify CIP length then you probably not gona get it. Just because you run a 338 dose not automatically mean your running CIP length.

If your going to change to CIP length magazines for your 338 you will need

CIP length mags
CIP chassis
You will probably need to modify your Defiance long action to work with the .125ish longer CIP mags. You will need to cut the feed ramp on the action forward to accommodate the longer mags
Click to expand...


I didn't know there was a difference between the two when I started. Can I run the heavier 300 gr bullets with the set up I have. Does this current style have any limitations? Will my standard Lapua Brass work and do I just seat the projectiles to fit?
 
  • Like
Reactions: DoubleD1234
They fit in the mag. The bolt will close if I wrench it down. Didn't buy a top of the line action to have issues like this though. My other two actions are butter and load up smooth as silk. This chasis is going back regardless though i want to be able to load the full length cartridges. Didn't go custom build to take what i could get. Defiance is a good company to deal with and Mile High is top knotch as well. I am sure all I will be out is my time.
 
You have any idea how far off the lands the bullet is that you just forced in the action? So did you check the OAL after you forced the bolt handle down? Did it get shorter? The action is the last thing to blame. The action will except a rnd of a given length what ever that is along with the mag will except a rnd of a given length. And if they dont except a rnd of the length as advertised then it is there problem. Doesnt sound like that is the problem. The barrel should of been chambered to match the max OAL of the other components in this build. So lets say the mag will except a rnd say 3.6" and the action is long enough to clear that also then the chamber should be cut shorter than that. And this is just the free bore that is what will determine your OAL. Now you want the chamber cut so you can reach the lands and still have a little wiggle room in the mag and action. Not recommending that you shoot this rnd on the lands or in the lands but you want room to chase the lands as the throat erodes. The setup you have may be just fine it sould like you load may have to alter. And keep in mind that if you push the bullet in further to the case the powder charge will have to change.
 
Ammo may not fit the mags but there is either a problem with you loading procedure or chamber if you are having to force the bolt, did you size your new brass?
 
There are two specs for the .338 Lapua Magnum:

CIP, or European specification (Lapua finalized the specs as a factory cartridge) and

SAAMI, or US specification (a Johnny-come-lately).

Who built your rifle may determine whose reamers got used.
 
Gi'day...

I'm a bit confused.

Originally you said "...ammo is dead nuts to specs. 3.680. I then measure the length of the AI AX 338 magazine and it measures 3.650" but now you are saying it fits in the mag?

I'm no expert on AI - just trying to understand, but isn't there only a CIP length for the AX chassis for .338LM?

The ammo I see, it's all 3.681"/93.50mm (some of it a bit longer, which is naughty) - why would you have a firearm that's shorter than this and non-CIP?

If people are out there building to non-CIP (it's been in CIP for YEARS!!) - what are they building to?
I haven't seen the SAAMI for the cartridge, but I don't imagine it's shorter (SAAMI site shows it as 'pending')
Or is this something special that AI did for the UK DoD?
 
The original .338 cartridge development was carried out in partnership between Lapua and Accuracy International and the round was shorter than the current CIP/SAAMI length. As a result all AW338 rifles and long action .338 legacy AICS have the magazine to take a shorter length .338. With the development of the AX338 we have changed to CIP length and that is the same for AX AICS.
Tom Irwin
Accuracy International
 
  • Like
Reactions: GrumpyOleFart and Nomad909
SAAMI spec is shorter in 2 milimeters if I remember correctly but you can load and shoot 300 grain bullets in SAAMI chamber, I know I shoot in my rifle 300's with no problem
 
To the OP,

You were quick to blame everyone about the issues you were experiencing with your rifle but it is quite clear the issues are a result of your ignorance. If you had done your due diligence beforehand you would not be asking AI or your smith to make it right.
 
  • Like
Reactions: Barney88PDC and kthomas
bertshortmag said:
You have any idea how far off the lands the bullet is that you just forced in the action? So did you check the OAL after you forced the bolt handle down? Did it get shorter? The action is the last thing to blame. The action will except a rnd of a given length what ever that is along with the mag will except a rnd of a given length. And if they dont except a rnd of the length as advertised then it is there problem. Doesnt sound like that is the problem. The barrel should of been chambered to match the max OAL of the other components in this build. So lets say the mag will except a rnd say 3.6" and the action is long enough to clear that also then the chamber should be cut shorter than that. And this is just the free bore that is what will determine your OAL. Now you want the chamber cut so you can reach the lands and still have a little wiggle room in the mag and action. Not recommending that you shoot this rnd on the lands or in the lands but you want room to chase the lands as the throat erodes. The setup you have may be just fine it sould like you load may have to alter. And keep in mind that if you push the bullet in further to the case the powder charge will have to change.
Click to expand...

Thank You for the advice. Basically what me and my buddy are running down. I figured that to be true on the powder charge. What a headache. The sierra and Lydman reloading guides don't show a single thing regarding the shorter cartridge re: powder charges or the shorter seating depth.
 
Last edited:
buffybuster said:
To the OP,

You were quick to blame everyone about the issues you were experiencing with your rifle but it is quite clear the issues are a result of your ignorance. If you had done your due diligence beforehand you would not be asking AI or your smith to make it right.
Click to expand...

Thank you Dad.
 
tomirwin said:
The original .338 cartridge development was carried out in partnership between Lapua and Accuracy International and the round was shorter than the current CIP/SAAMI length. As a result all AW338 rifles and long action .338 legacy AICS have the magazine to take a shorter length .338. With the development of the AX338 we have changed to CIP length and that is the same for AX AICS.
Tom Irwin
Accuracy International
Click to expand...

Thanks for the clarification. Awesome having the people who make the product on a site like this. Question I have is how did I wind up with a non CIP AX Chasis? It sounds like you are saying the AX chasis are all CIP length? I hope I am not misquoting you just trying to understand.

Thank You
 
Last edited:
  • Like
Reactions: Nomad909
sinister said:
There are two specs for the .338 Lapua Magnum:

CIP, or European specification (Lapua finalized the specs as a factory cartridge) and

SAAMI, or US specification (a Johnny-come-lately).

Who built your rifle may determine whose reamers got used.
Click to expand...


Funny thing is Defiance never even asked me which set up I was running when I called them to initially do the build.Thats kind of weird? ALl I told them was that I wanted to put it on an AX Chasis.
 
blackblue said:
Ammo may not fit the mags but there is either a problem with you loading procedure or chamber if you are having to force the bolt, did you size your new brass?
Click to expand...

Yes, according to the specs in the Sierra reloading manual. Brass was brand new Lapua brass and was nearly perfect out of the box.
 
farmerbrown said:
Gi'day...

I'm a bit confused.

Originally you said "...ammo is dead nuts to specs. 3.680. I then measure the length of the AI AX 338 magazine and it measures 3.650" but now you are saying it fits in the mag?

I SEATED THE PROJECTILES DOWN FURTHER AS ONE OF THE EARLIER POSTERS SUGGESTED.

I'm no expert on AI - just trying to understand, but isn't there only a CIP length for the AX chassis for .338LM?

I DIDNT KNOW THERE WERE 2 CHASIS EITHER WHEN I BOUGHT THE ACTION. I CALLED MILE HIGH AND SAID I NEEDED A AX CHASIS FOR A 338 LAPUA BUILD I WAS DOING. THEY DID NOT ASK ME WHICH AX 338 CHASIS I NEEDED. I HAVE SPENT OVER 20K WITH THEM THIS YEAR AND THEY ALWAYS TREAT ME RITE. I JUST WANT TO GET THE CORRECT CHASIS. NOT EXPECTING ANY ISSUE AS THEIR CUSTOMER SERVICE IS AWESOME.

The ammo I see, it's all 3.681"/93.50mm (some of it a bit longer, which is naughty) - why would you have a firearm that's shorter than this and non-CIP?

WISH I WOULD HAVE KNOWN.

If people are out there building to non-CIP (it's been in CIP for YEARS!!) - what are they building to?
I haven't seen the SAAMI for the cartridge, but I don't imagine it's shorter (SAAMI site shows it as 'pending')
Or is this something special that AI did for the UK DoD?
Click to expand...

You have some of the same questions I do?
 
pyrofx said:
First guess is ...... CIP length round . Non CIP magazine.
Chamber cut for non CIP

Greg
Click to expand...

That sounds about right to me.

If I were you, I would load a few rounds to a shorter OAL and see how bolt closure is.

I'd also call the builder and consult him on what the chamber dimensions are. This could be a quick answer to what's happening.

It sucks that things aren't what you hope, but patience will be your friend in getting this all resolved.

I would venture to guess that the problems have pretty much nothing to do with the action and more with the chamber specs.
 
Are you getting rifling marks on the bullets that you tried to chamber? If you try to chamber a sized case without a bullet, does the bolt close OK?
 
I'm not sure what you mean by a dimple on the rim. What I'm curious about is whether or not the bullets are getting jammed into the rifling as you try to close the bolt.

How are you sizing them and what dies are you using? If you're full length resizing with a properly set up die, then there's a problem with that chamber. I'm using a Forester Ultra die set. I have mine set so that the shoulder is being set back just the minimal amount for the bolt to close. I'm assuming since this is your third build that you know what you're doing with your reloads.
 
Not familiar with those. Are they full length and if so, do you have them adjusted so that the mouth of the die is contacting the shell holder and camming over?
 
Too much assuming going on. Assuming is how this mess got started.

If the sized cases are not chambering, then have brand new cases been tried in the chamber? If those don't close, then you need to talk with the smith and get a set of GO/NOGO gauges. A reamer print would also be helpful. If the chamber headspace checks out, then you need to start checking your reloading practices, check the headspace of your sized brass.

Whether the chamber was cut using SAMMI or CIP specifications becomes irrelevant if it was not cut properly. If the chamber was cut to SAMMI or CIP specification, either will sling a 300gr bullet to beyond a mile.
 
  • Like
Reactions: VargmatII
The gunsmith should have never let the rifle leave the shop without verifying headspace. He should have the GO/NOGO gauges and used them during the build. If not, he's not a gunsmith...
 
  • Like
Reactions: VargmatII and Barney88PDC
Badshot308 said:
Not familiar with those. Are they full length and if so, do you have them adjusted so that the mouth of the die is contacting the shell holder and camming over?
Click to expand...

Yeah, I triple check my reload specs every single time. Never had a problem with my 308, 300 win mag, 9mm, 45 auto, or 50 AE reloads.
 
Last edited:
buffybuster said:
Too much assuming going on. Assuming is how this mess got started.

If the sized cases are not chambering, then have brand new cases been tried in the chamber? If those don't close, then you need to talk with the smith and get a set of GO/NOGO gauges. A reamer print would also be helpful. If the chamber headspace checks out, then you need to start checking your reloading practices, check the headspace of your sized brass.


Whether the chamber was cut using SAMMI or CIP specifications becomes irrelevant if it was not cut properly. If the chamber was cut to SAMMI or CIP specification, either will sling a 300gr bullet to beyond a mile.
Click to expand...


Yeah I am using brand new Lapua brass that has been sized with Redding Competition Dies.
 
Do you have any factory ammo you can try in the rifle? The only two boxes of factory 338 Lapua that I every bought were Blackhills brand. One was a 250 gr SMK and the other was a 300 gr SMK. Those were loaded to around 3.6" to fit through the non CIP AI magazines that were available at the time. Even if the only factory ammo you can obtain is loaded to CIP length, you should be able to single load them without a problem. If factory ammo won't chamber, then it's definitely time to contact the builder.
 
Ok,


just to be clear as I am now confused: A full length resized piece of brass, with no bullet...just the sized brass, will not chamber into your rifle far enough for you to close the bolt?

That is a critical piece of information that needs to be clarified. That changes the game.
 
smokebomb said:
Ok,


just to be clear as I am now confused: A full length resized piece of brass, with no bullet...just the sized brass, will not chamber into your rifle far enough for you to close the bolt?

That is a critical piece of information that needs to be clarified. That changes the game.
Click to expand...


no it will not
 
Just to clarify something, are those full length dies or the neck sizing dies with the removable neck bushings?
 
Badshot308 said:
Do you have any factory ammo you can try in the rifle? The only two boxes of factory 338 Lapua that I every bought were Blackhills brand. One was a 250 gr SMK and the other was a 300 gr SMK. Those were loaded to around 3.6" to fit through the non CIP AI magazines that were available at the time. Even if the only factory ammo you can obtain is loaded to CIP length, you should be able to single load them without a problem. If factory ammo won't chamber, then it's definitely time to contact the builder.
Click to expand...


Don't have any factory ammo. I reload for all of my rifles so I just bought 500 pieces of Lapua Brass, 1500 300 SMK, and 16 lb.s of IMR 7828 powder. I have never had any problems with any of my reloads.
 
Ah,

In that case your "gunsmith" needs to be notified. Your chamber is not headspaced to proper depth.

As an answer to CIP vs non CIP, it's your call there. I happily run my .338 lapua loaded to 3.6" OAL. My magazines could handle 3.85" but I start kissing lands at 3.62" with 300 gr SMKs and the accuracy has been phenominal. Good luck!
 
Well, sounds like you have a headspace problem. Only way to tell is with a set of Go/No-Go gauges.
 
This might not help with your current problem, but after reading this entire thread I suggest you spend some time on the hand loading forum. There is a ton of good info on there I think you could use. I also suggest you put those reloading manuals on the shelf, get the right tools, and learn to measure all the specs of the specific gun for which you are loading. This eliminates the guessing game and will give you very precise ammo.
 
I concur that the chamber is likely cut to original .338 spec, magazine length be damned. Probably about what I have in my AIAX chassis and Surgeon built action .338 LM. Best COAL is between 3.595 and 3.610 using a Sierra or Lapua Scenar bullet. The best load for accuracy has been 89 grains of H-1000 for my rifle. If you want a longer chamber to load out VLD bullets and 250 grainers to longer lengths and push the envelope on what exactly is a hot round in a .338, get your chamber re-reamed or have one the the world class tool and die guys (PTG comes to mind) cut you a custom reamer and give it a whirl. The good guys at Surgeon told me they had used a Berger seated out to 3.710 in one of their rifles. Every bullet strikes the lands differently due to the bullet ogive. Gotta get a OAL gauge and see what you have length wise before loading to a specific COAL for a given bullet. 9 out of 10 of the members here can probably expound on this info 1000% time better than I can. Try the reloading forum for really great intel. Never stop trying to learn, even if you got it wrong you can usually fix it. Unless it is made of plastic.
 
You must log in or register to reply here.

Similar threads

surgeon260
338 Lapua AI Build Advice
Replies
1
Views
248
jbuck88
jbuck88
B
338 lapua build
Replies
5
Views
342
Thump_rrr
T
P
SOLD Defiance .223 barreled action SOLD
Replies
5
Views
1K
precisionpaper
P
R
Checking SD with Brand New Brass, or Once Fired???
Replies
6
Views
226
918v
918v
A
338 Lapua Ackley Improved questions and request for load data
Replies
8
Views
335
Dogtown
Dogtown
Top Bottom
Back