338 lapua reciever question

[Willoughby]

so I want to try a 338 lapua -will a small shank receiver work ? or are they a special 338 only receiver's thanks

[Ted_Feasel]

so I want to try a 338 lapua -will a small shank receiver work ? or are they a special 338 only receiver's thanksI know savage 111 In 338 LM is large shank

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[Ted_Feasel]

so I want to try a 338 lapua -will a small shank receiver work ? or are they a special 338 only receiver's thanksAre you wanting to buy like a target action for. A precision build?

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[tobnpr]

Do some serious research/due diligence before assembling a chambering with high bolt thrust like the .338 LM on any receiver/bolt not designed for it.

That aside, I am not aware of any manufacturer offering a "prefit", chambered Savage barrel in that chambering. Ostensibly, so that relatively inexperienced individuals screwing parts together don't end up with a bolt blown through their forehead.

[Ted_Feasel]

Do some serious research/due diligence before assembling a chambering with high bolt thrust like the .338 LM on any receiver/bolt not designed for it.

That aside, I am not aware of any manufacturer offering a "prefit", chambered Savage barrel in that chambering. Ostensibly, so that relatively inexperienced individuals screwing parts together don't end up with a bolt blown through their forehead.They dont have them orechambered but you can get them with bore and rifling and have a gunsmith ream the chamber I do believe

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[efm77]

A standard small shank action is not a good idea. The Lapua should only be built on the action specifically made for it. Many say that Savage should have increased the overall size of the action for the Lapua but they didn't. They did, however, change to a better heat treatment and thicker locking lugs, as well as making the ports smaller in the receiver for added strength. There are barrel makers that will make pre-fit barrels for them. I have 2 McGowen barrels in my safe right now chambered for 338 Lapua. If you do it on a regular action, you're risking lug setback which can lead to headspace problems and the small shank barrel doesn't have chamber walls thick enough for the pressure either. I have two of them, a 110 LRH, and a 112 Magnum target. But they are made from the factory specifically for the Lapua round, and I say again, you should not do it with a regular action, but do it with the Lapua specific action only.

[Shortbox4x4]

I was doing testing with 338 Lapua back around 2009. I put a barrel on a older single shot 112V J series. That one gun is my test rifle. I set it up with out the barrel nut so the breech diameter of the barrel at the receiver was 1.250” o.d and being a single shot it gave me more confidence with the bolt lug engagement vs. Rem. 700’s where you have to open up/rework the feed ramp which I don’t like. That makes that bottom lug area have less support.

I opened up a mag bolt face to 338 Lapua and polished the extractor so it would snap over the rim. It chambered and ejected empty cases with no issues.

When Savage came out with they’re factory rifle....yes it’s a large shank but the receiver o.d. And lug area is the same. So it’s not any stronger per say.

The large shank is 1.120 vs. the 1.055” thread on the small shank (which is only about .005” smaller than a Remington thread. If you use the factory Savage barrel nut even on a large shank that still limits you to a 1.120” breech diameter. By not using the barrel nut like I did at least I could go up to a 1.250” breech diameter. Heck you can even go up to 1.350” diameter on the barrel. I’ve done 1.3” before on a Savage.

That all being said it was for testing I did prior to PSR1. If I was going to have a dedicated 338 Lapua or Norma I’d build it on a bigger receiver.

Later, Frank
Bartlein Barrels

[yobuck]

I was doing testing with 338 Lapua back around 2009. I put a barrel on a older single shot 112V J series. That one gun is my test rifle. I set it up with out the barrel nut so the breech diameter of the barrel at the receiver was 1.250” o.d and being a single shot it gave me more confidence with the bolt lug engagement vs. Rem. 700’s where you have to open up/rework the feed ramp which I don’t like. That makes that bottom lug area have less support.

I opened up a mag bolt face to 338 Lapua and polished the extractor so it would snap over the rim. It chambered and ejected empty cases with no issues.

When Savage came out with they’re factory rifle....yes it’s a large shank but the receiver o.d. And lug area is the same. So it’s not any stronger per say.

The large shank is 1.120 vs. the 1.055” thread on the small shank (which is only about .005” smaller than a Remington thread. If you use the factory Savage barrel nut even on a large shank that still limits you to a 1.120” breech diameter. By not using the barrel nut like I did at least I could go up to a 1.250” breech diameter. Heck you can even go up to 1.350” diameter on the barrel. I’ve done 1.3” before on a Savage.

That all being said it was for testing I did prior to PSR1. If I was going to have a dedicated 338 Lapua or Norma I’d build it on a bigger receiver.

Later, Frank
Bartlein Barrels
Interesting post.
I agree on the Rem action as for the larger cases, and it puzzles me as to why the cartridge designer of the 300/338 Norma chose to use a 700 action?
Explain large? As in custom? Or as in bolt diameter?

[Shortbox4x4]

Interesting post.
I agree on the Rem action as for the larger cases, and it puzzles me as to why the cartridge designer of the 300/338 Norma chose to use a 700 action?
Explain large? As in custom? Or as in bolt diameter?

No clue as to your question on why a cartridge designer of the 300/338 Norma and or Lapua cases would’ve used a 700 type action. If memory serves me right the first commercial type rifle chambered in 338 Lapua was the AI L115a3. I don’t recall the receiver/barrel thread specs off hand but I do know even the older AI rifles had bolt with larger body diameters than a Rem700 or a Savage 110 or Win.70. The AI bolt and again going off of memory has like a .775” or .800” bolt diameter. I’ll have to measure one to be sure but that is bigger then the .700” diameter of the Rem. Or Sav. Bolt body.

You have actions now a days with a larger receiver tenon thread like the Stillers Tac30, Surgeon XL etc...that use a 1.125” diameter thread. So usually the breech diameter of the barrel starts out at 1.3” to 1.350” and can usually go up a little more. The BAT Model M action has a 1.125” thread as well. My take on having a larger receiver/barrel thread gives you more meat (wall thickness) from the id to do of the bore to the barrel. Some actions with the larger tenon threads also ending up having a larger diameter to the bolt as well.

To me having this extra meat from the bore to od of the barrel and a bigger bolt diameter/bigger lugs gives you more surface area for strength. Also with the pressures that some of these rounds are running at with the larger case diameter....the larger barrel diameter to me gives/stretches less per say. So case/chamber expansion is less or per say equal to a standard caliber/action set up. This helps keep case expansion in check and to me helps reliability and you will see it at times when you reload/resize the cases.

Apply the same logic to reloading/sizing dies. When you start getting into the 338 Lapua and bigger cases the standard 7/8-14 threaded sizing dies are known to crack. Also the more problems with guys getting the cases stuck in the sizing die. It’s usually not if they will it’s when they will. It’s all stress and something has to give.

[yobuck]

No clue as to your question on why a cartridge designer of the 300/338 Norma and or Lapua cases would’ve used a 700 type action. If memory serves me right the first commercial type rifle chambered in 338 Lapua was the AI L115a3. I don’t recall the receiver/barrel thread specs off hand but I do know even the older AI rifles had bolt with larger body diameters than a Rem700 or a Savage 110 or Win.70. The AI bolt and again going off of memory has like a .775” or .800” bolt diameter. I’ll have to measure one to be sure but that is bigger then the .700” diameter of the Rem. Or Sav. Bolt body.

You have actions now a days with a larger receiver tenon thread like the Stillers Tac30, Surgeon XL etc...that use a 1.125” diameter thread. So usually the breech diameter of the barrel starts out at 1.3” to 1.350” and can usually go up a little more. The BAT Model M action has a 1.125” thread as well. My take on having a larger receiver/barrel thread gives you more meat (wall thickness) from the id to do of the bore to the barrel. Some actions with the larger tenon threads also ending up having a larger diameter to the bolt as well.

To me having this extra meat from the bore to od of the barrel and a bigger bolt diameter/bigger lugs gives you more surface area for strength. Also with the pressures that some of these rounds are running at with the larger case diameter....the larger barrel diameter to me gives/stretches less per say. So case/chamber expansion is less or per say equal to a standard caliber/action set up. This helps keep case expansion in check and to me helps reliability and you will see it at times when you reload/resize the cases.

Apply the same logic to reloading/sizing dies. When you start getting into the 338 Lapua and bigger cases the standard 7/8-14 threaded sizing dies are known to crack. Also the more problems with guys getting the cases stuck in the sizing die. It’s usually not if they will it’s when they will. It’s all stress and something has to give.
Which also means a new larger loading press, $250 custom dies, new trimmer, new hand priming tool, not to mention the brass cost for a real 338.
And count on about 3 loads at peak performance before chucking the brass anyway
But then you wont need good eyes to see the difference between 2850 and 3250 with 300 grains at 1500 or more either if your into that stuff.
It’s a shame that everybody wanting a long range gun cant go watch them fly first, before they commit to buying one.

[efm77]

All good points. My point about the large shank is not that it makes it any stronger at the receiver ring. My thought is that Savage did it be able to keep the barrel nut and still have thicker chamber walls for that portion that extends beyond the receiver ring. I agree that a larger action overall would be the better option. However, I've seen quite a few Savages in 338 Lapua (their factory action designed for the Lapua that is) with quite a number of rounds through them with zero issues. Something makes me think that if people are having issues with lug setback etc, (when using the actions that came from the factory made for the Lapua, not putting a Lapua barrel on a regular Savage action) are using over loaded rounds, or have oil in their chamber restricting the brass from gripping the chamber, etc. I say that because I can't imagine Savage continuing to make them and not recalling them if it was found to be inherently dangerous.

As kind of a side note, does anyone know the dimensions of the RPR that's chambered for the Lapua in comparison to the Savage? I'm curious because I've thought about getting one of them too and haven't heard of any issues with them and Ruger has always been know for building stout actions.

[J.Baker]

I was doing testing with 338 Lapua back around 2009. I put a barrel on a older single shot 112V J series. That one gun is my test rifle. I set it up with out the barrel nut so the breech diameter of the barrel at the receiver was 1.250” o.d and being a single shot it gave me more confidence with the bolt lug engagement vs. Rem. 700’s where you have to open up/rework the feed ramp which I don’t like. That makes that bottom lug area have less support.

I opened up a mag bolt face to 338 Lapua and polished the extractor so it would snap over the rim. It chambered and ejected empty cases with no issues.

When Savage came out with they’re factory rifle....yes it’s a large shank but the receiver o.d. And lug area is the same. So it’s not any stronger per say.

The large shank is 1.120 vs. the 1.055” thread on the small shank (which is only about .005” smaller than a Remington thread. If you use the factory Savage barrel nut even on a large shank that still limits you to a 1.120” breech diameter. By not using the barrel nut like I did at least I could go up to a 1.250” breech diameter. Heck you can even go up to 1.350” diameter on the barrel. I’ve done 1.3” before on a Savage.

That all being said it was for testing I did prior to PSR1. If I was going to have a dedicated 338 Lapua or Norma I’d build it on a bigger receiver.

Later, Frank
Bartlein Barrels

Actually, your breech diameter was still 1.055", just the shoulder abutment of the barrel (where it contacts the face of the action) is 1.250".

Also, All of the factory .338 LM's use the new heavy magnum bolt head which has longer (front to rear) lugs for additional sheer strength. Unfortunately this change did nothing to make the action stronger as it added zero surface area to the lugs where they contact the ramp abutments.

There's a reason all of the custom action makers make specific actions for the .338 Lapua Mag size cartridges to prevent lug setback - which is a common problem with .338 LM's built on Savage actions.

[tobnpr]

There's a reason all of the custom action makers make specific actions for the .338 Lapua Mag size cartridges to prevent lug setback - which is a common problem with .338 LM's built on Savage actions.

Evidence of this claim?

[Willoughby]

so it is a 338lm specific receiver ,
this may be the best answer to original question -- is it a 338:LM specific receiver
-or ? Savage uses a better heat treatment and thicker locking lugs, as well as making the ports smaller in the receiver for added strength-
is it a 338:LM specific receiver - It would have to be a Savage - so I know what I need now thanks

[efm77]

so it is a 338lm specific receiver ,
this may be the best answer to original question -- is it a 338:LM specific receiver
-or ? Savage uses a better heat treatment and thicker locking lugs, as well as making the ports smaller in the receiver for added strength-
is it a 338:LM specific receiver - It would have to be a Savage - so I know what I need now thanks



Yes the one that Savage makes for the Lapua is specifically for it with different heat treatment, smaller ports, and thicker locking lugs.


As Tobnpr said, I'd like to see the evidence too. I've said this on several threads. I respect the knowledge of those on here and understand the concern but have yet to see any proof or hear of it anywhere else other than this forum. I see people shooting them many many rounds to no detriment and no one talks of any headspace or lug setback issues. And again, I ask, if it's so dangerous (I'm referring to the receivers that Savage makes specifically for the Lapua round), then why hasn't Savage recalled them?

I have also ordered a Ruger Precision in 338 Lapua and out of curiosity, will measure the 3 lugs on its bolt and as well as the 2 lugs on my Savage Lapua bolt and compare surface area measurements to see if it is any more than the Savage overall.

[Shortbox4x4]

Actually, your breech diameter was still 1.055", just the shoulder abutment of the barrel (where it contacts the face of the action) is 1.250".

You are correct and I should’ve made the point/clarified that in my post. Thanks for bringing up that point as it is important.

Later, Frank

[sharpshooter]

Even if the receiver were 2" in dia, the first ring of steel around the chamber is what will stretch. Having a smaller tenon will add to bolt thrust. The bolt thrust for a .338 Lapua is aprox 12,000 psi. The bolt thrust for a standard magnum, i.e, .300 win mag is 9400 psi.
That is per square inch. Now when you concentrate that pressure down to the area of the bolt lugs ( .135 square inches) is produces over 91,000 lbs of load to that area (for the Lapua) and 70,000 for the .300 WM.
To make things worse, take into consideration that a Savage bolt head floats. Unless the receiver is a single shot, all repeaters will have a weaker lug abutment on the bottom. This weaker abutment flexes upon firing, and subsequently the bolt head follows it, transferring the majority of the load to the top lug abutment. The bottom lug abutment on the .338's are actually weaker than a standard caliber, as the feed ramp was moved ahead about .050" to accommodate the longer case.
I have spoken with several custom action makers and all have came up with the bare minimums they would use for a case the size of a .338 Lapua. Bolt body dia. of .750", barrel tenon of 1.125, and bolt lug diameter of 1.125. These specs result in another 33% of surface area and reduce the pressure on the lugs by the same amount down to 68,000.
Now this big question: Is lug setback dangerous? In cases of "normal pressure levels", the amount of setback, or the depth of the foot print is usually less than .001", but I have worked on receivers where it was in excess of .004". Is this going to cause a dangerous situation and maybe a catastrophic failure? In reality...probably not because nobody shoots one enough to get it to the fatigue point, but it will get hard to extract cases, that is a sure bet.
I have seen lug set back in all of the larger cases calibers, RUM's, WSM's and especially the .338's. You don't have to take my word for it, take your barrel off and you will find a lug impression on the top lug abutment, and maybe on the bottom. It may not be very deep at this time, but it will be there none the less.

[efm77]

Even if the receiver were 2" in dia, the first ring of steel around the chamber is what will stretch. Having a smaller tenon will add to bolt thrust. The bolt thrust for a .338 Lapua is aprox 12,000 psi. The bolt thrust for a standard magnum, i.e, .300 win mag is 9400 psi.
That is per square inch. Now when you concentrate that pressure down to the area of the bolt lugs ( .135 square inches) is produces over 91,000 lbs of load to that area (for the Lapua) and 70,000 for the .300 WM.
To make things worse, take into consideration that a Savage bolt head floats. Unless the receiver is a single shot, all repeaters will have a weaker lug abutment on the bottom. This weaker abutment flexes upon firing, and subsequently the bolt head follows it, transferring the majority of the load to the top lug abutment. The bottom lug abutment on the .338's are actually weaker than a standard caliber, as the feed ramp was moved ahead about .050" to accommodate the longer case.
I have spoken with several custom action makers and all have came up with the bare minimums they would use for a case the size of a .338 Lapua. Bolt body dia. of .750", barrel tenon of 1.125, and bolt lug diameter of 1.125. These specs result in another 33% of surface area and reduce the pressure on the lugs by the same amount down to 68,000.
Now this big question: Is lug setback dangerous? In cases of "normal pressure levels", the amount of setback, or the depth of the foot print is usually less than .001", but I have worked on receivers where it was in excess of .004". Is this going to cause a dangerous situation and maybe a catastrophic failure? In reality...probably not because nobody shoots one enough to get it to the fatigue point, but it will get hard to extract cases, that is a sure bet.
I have seen lug set back in all of the larger cases calibers, RUM's, WSM's and especially the .338's. You don't have to take my word for it, take your barrel off and you will find a lug impression on the top lug abutment, and maybe on the bottom. It may not be very deep at this time, but it will be there none the less.


Thank you for the elaboration Sharpshooter. Do you have an estimate of how many firings it would take to finally fail? I will be sure to check mine when I change barrels as well but since I haven't pulled the barrel off of my Lapuas yet, do you have any photos of ones you've worked on? I'd be curious to see just how bad it looks.

[sharpshooter]

There are way too many variables to consider before one could could even make an estimate. All the ingredients have to be present for a "perfect storm". For example: I witnessed an Axis rifle "grenade" at the local shooting range. A guy was shooting a 30-06, when the rifle exploded, causing the barrel to disconnect and launch forward 10 feet, while the receiver whizzed past his head the other way. Unfortunately he was holding the rifle right under the magazine, (which by the way is escape route for uncontained gas )and when it came apart, it broke 2 of his fingers and split his hand. He also suffered a few more minor cuts and contusions. Lucky for him nothing hit him in the face, and the fact that his son was with him, who just happens to be an EMT.
Initial investigation showed that the the receiver had split in the lower right hand corner of the raceway, the same place they always split, through the guide fin cut. The bolt was still in lock position, with the lugs wedging the receiver apart. The barrel, though detached, was unscathed other than a scratch at the muzzle where it hit the concrete. The threads were never smeared or disturbed and the chamber had no swell. The first thing I looked for was a barrel obstruction, and there was none, only the front end of the case still in the chamber.
I know from speaking with several of the engineers, it takes a minimum of 100,000 psi for the receiver to fail, and at least double proof pressure ( 150,000 psi) for lugs to shear. At that point it makes no difference once the receiver fails, it's already catastrophic.
Final investigation revealed 3 factors that contributed to the accident. The shooter said he was shooting some factory loads and some hand loads. I found 3 rounds that blew out of the magazine when it went. One was a Remington factory 150 gr., and the other 2 were handloads. The handloads consisted of 57 grs. of H380, in a 1966 LC case and a Hornady 150 bullet.
While H 380 would not be my choice for 30-06, he stated he also had a 22-250 and wanted to use it in both rifles. I checked several reloading manuals and none of them have any loads with over 53 grs. He showed me the Hogden powder canister that had a load listed on it for a 165 gr. bullet, with 56.4 grs. This threw up a red flag, indicating this could be a misprint, no only that, being a novice reloader, he did not begin with a starting load and work his way up. Typically in normal circumstances, an over load like this would not normally cause this kind of damage, but it would lock up the bolt and rupture a primer, still something I want no part of.
The next thing was the cartridge case. Lake City 1966 that was purchased at a local gun show. "The guy told me these were already sized, cleaned, and ready to reload." is what he told me. The fact is that the brass was older the he was. Old brass tends to work harden just with age, and besides that, who knows how many times they were fired and did they have any defects like a partial case seperation? Being a novice, he didn't know any better, to him, brass is brass and cheaper is better.
The 3rd nail in the coffin was the fact that the cases were sized to the point the shoulder had been bumped back .014", creating a headspace problem. That unto itself will cause a case separation, but not necessarily a catastrophic failure, but when you add up all the contributors it spells disaster.
Sory, no pics...my camera took a crap about 6 months ago.

[efm77]

OK so this brings another question to my mind Sharpshooter. If the Savage, and Remington too from what I hear, are marginal for this size cartridge, why is the Weatherby Mark V considered to be strong enough for cases this size? It's not a bigger action so I've never understood that. It has the same size receiver diameter IIRC, or very close. It also has the same size barrel shank and thread pitch as a Remington. And from what I've read about the measurements taken on the surface area of the 9 locking lugs, there's no more bearing surface area there than with a dual lug bolt. So what's the deal with it? Some sort of super duper heat treatment? That's about all I can think of. I read a lot of writings by, I believe it was Kirby Allen, who had done a lot of testing and his measurements were showing the Remington lugs to actually have more surface area than the Mark V's 9 lugs. Not trying to be argumentative, but am just genuinely curious and want to learn more.