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yobuck
04-10-2020, 05:55 PM
Well I must respectfully disagree with a few of your points as well. Many references can be found about how much an action can handle to the point of destruction. Several times over the years I've read of engineers for manufacturers destruction testing their actions. Mos bolt actions will go to around 120k PSI before they completely blow, but you'd likely start seeing lug setback before that.

As for the 378 Weatherby case. I could be wrong because it has been a while since I've read up on it and am not currently researching it while responding, but I'm pretty sure I read that Roy went with the Magnum Mauser action for those cases, which is a bigger action than the standard.

As for the Savage action, it's not their standard action either. Yes it is the same outside dimension but that's about where it ends. If there wasn't something to that size case needing more strength they wouldn't have built them the way they do and just went with their standard long action. It undergoes a better heat treatment to make it stronger/harder. The locking lugs are longer front to back for better shear strength. The ejection port is much smaller to give it a more solid top behind the top lug abutment making the action more rigid and stronger. And the barrel tenon is larger for the Lapua's and WSM's (1.125" vs 1.055")

I have no proof, but personally think Savage made the right steps to make their Lapua action strong enough to handle it. However, I do take to heart what experienced gunsmiths say about it being marginal. To my knowledge, only Savage, Remington, and Weatherby make them on their same size actions. Any other manufacturer goes to a larger size action, including customs like Stiller. I have 3 Lapuas. Two Savages and one RPR and I can tell you that Ruger must have taken it to heart as well because the Magnum RPR receiver is larger than the Savage and it has more bearing surface area with the 3 locking lugs (I've measured and compared them). Again, they must be just strong enough though because Savage, Remington, nor Weatherby have ever recalled them that I know of. So as sort of an agreement with your point, if it were a liability to where they were afraid of getting sued, they'd likely recall them which hasn't happened.

Now does that mean the Savage is no good? No. But there is something to the greater amount of bolt thrust generated by this larger case head or they wouldn't beef up the action like they do and Ruger wouldn't have gone to a larger action. I've always suspected Weatherby's claims of being the strongest to be mostly a crock. The receiver is no bigger than a Remington or Savage, neither is the barrel tenon. The 9 locking lugs are so small, their actual bearing surface area is less than a Remington's or Savage's when all 9 are in contact which is rare.

As for the Mark V action, the gunsmiths ive known who use them for the larger cartridges like the 30x378, (claim) they lap the lugs.
And the reason they prefer them over other non custom actions is bolt diameter. That said i do know gunsmiths like Bruce Baer for example who dont care for them, claiming them to be no stronger than a Rem.
Ive never heard of a Rem having setback issues with a factory magnum cartridge however.
I have one Mark V chambered in 300 Norma, which has become my favorite LR hunting cartridge.
Note that i didnt say best, just favorite.
Actually, its nothing more than a shortened case version of the 30x378 with a traditional shoulder.

Being a curious person who has always had the bad habit of asking why, my question to you would be why three 338 Lapuas?
Would not just one 338 built on a custom action make more sense?
We can talk about hype, and i certainly agree that a whole lot of it takes place with the marketing of long range equiptment.
Including some of the cartridges, the 338 Lapua being one of them imop.
And every gun maker has clamored for a seat on the LR band wagon.
Arguably at least Wetherby started out there. But even they for example have recently introduced the 6.5x300 cartridge.
50 years ago it was the most popular long range hunting gun cartridge on the planet, which at that time consisted pretty much of only Pa.
And by about 1975, it was dead and buried there as being a good long range hunting cartridge, and you simply wont find any being used there today.
Ditto for all the other hot 6.5s, and why would you when there are better ones costing the same to buy or build.
Id suggest you sit behind and watch as a few different 338s are being shot at serious distance one after another at the same target.
You might be asking yourself why one of these, when i could have one of those ?
But not on a Savage action.

efm77
04-13-2020, 08:44 AM
As for the Mark V action, the gunsmiths ive known who use them for the larger cartridges like the 30x378, (claim) they lap the lugs.
And the reason they prefer them over other non custom actions is bolt diameter. That said i do know gunsmiths like Bruce Baer for example who dont care for them, claiming them to be no stronger than a Rem.
Ive never heard of a Rem having setback issues with a factory magnum cartridge however.
I have one Mark V chambered in 300 Norma, which has become my favorite LR hunting cartridge.
Note that i didnt say best, just favorite.
Actually, its nothing more than a shortened case version of the 30x378 with a traditional shoulder.

Being a curious person who has always had the bad habit of asking why, my question to you would be why three 338 Lapuas?
Would not just one 338 built on a custom action make more sense?
We can talk about hype, and i certainly agree that a whole lot of it takes place with the marketing of long range equiptment.
Including some of the cartridges, the 338 Lapua being one of them imop.
And every gun maker has clamored for a seat on the LR band wagon.
Arguably at least Wetherby started out there. But even they for example have recently introduced the 6.5x300 cartridge.
50 years ago it was the most popular long range hunting gun cartridge on the planet, which at that time consisted pretty much of only Pa.
And by about 1975, it was dead and buried there as being a good long range hunting cartridge, and you simply wont find any being used there today.
Ditto for all the other hot 6.5s, and why would you when there are better ones costing the same to buy or build.
Id suggest you sit behind and watch as a few different 338s are being shot at serious distance one after another at the same target.
You might be asking yourself why one of these, when i could have one of those ?
But not on a Savage action.

I wound up with 3 because I kind of went down a rabbit hole with them lol. I like the round and started out with the 112 Magnum Target because of the price of the rifle and didn't mind it being a single shot since I wasn't planning on shooting high volume or rapid fire with it anyway. Then I got to thinking I wanted one to hunt with that was a repeater and a little lighter so I got a 110LRH. Then I started getting interested in the RPR because the looks and design of the rifle grew on me. I also liked how Ruger had actually up-sized the action to better suit this cartridge size. It's about 1/10" larger in diameter. Might not sound like much but in terms of added strength with steel it's pretty significant. It's more along the size of some of the custom actions. It also has around 30% more bearing surface area with its locking lugs vs the Savage (I measured both to compare).

I too have heard of gunsmiths lapping the lugs on a Mark V and said it was very difficult if not downright impossible to get even contact with all 9. And even so, the lugs are so small the actual surface area is no greater. I don't believe the size of the bolt body contributes anything to strength as all of the force is on the lugs and their abutments. It does make for smooth cycling though. As for the Remington 700, I have heard some smiths say the same about it as some on here say about the Savage when it comes to the Lapua size cases about lug setback. Never witnessed it myself, but there are some out there that are concerned about it. It's not just about the PSI as the Lapua and 378 size cases operate at similar pressures as smaller cartridges. But when you have that same amount of pressure spread out over a larger surface area due to the case head size, it puts greater thrust force on the bolt face. Not being argumentative, just stating my observations, and what I have read from others more knowledgeable than me.

As for watching others shoot their different 338's, I have no desire to do that other than for the fun of it. I don't plan on using a custom action nor do I compete. I shoot for the fun of it and I just like the 338 caliber. Always have. To each their own. The actions I have serve me just fine.

steve_podleski
09-23-2020, 07:52 PM
Just started reloading for the Savage M112 Target action in 338LM. Bought this rifle a few weeks ago and have not yet shot any rounds through it. I used the Hornady tool to measure seating depth for the Sierra 250MK and the round looked very short with OAL of 3.526" I think SAAMI spec has 3.681". Is the throat to short for this bullet? Has anyone else shot this rifle?

efm77
09-25-2020, 02:03 PM
Just started reloading for the Savage M112 Target action in 338LM. Bought this rifle a few weeks ago and have not yet shot any rounds through it. I used the Hornady tool to measure seating depth for the Sierra 250MK and the round looked very short with OAL of 3.526" I think SAAMI spec has 3.681". Is the throat to short for this bullet? Has anyone else shot this rifle?

I have the 112 Magnum Target. I've been shooting 250 grain Hornady BTHP match bullets. I think they're similarly shaped to the SMK. I'm at work and don't have my notes with me but I have just been loading them to the OAL listed in the Hornady Manual and they've been chambering fine.

E6Chevron
06-07-2022, 02:51 AM
Savage believes that the new Impulse Hexlock 6 ball Straight-Pull action is strong enough for 300 WSM and recently added the 6.5 PRC, 300 PRC and 338 Lapua. All four of these cartridges use the Large Shank (1 1/8" -20 thread) barrels as used in some of the 110 rifles. However, the Impulse has these barrels thread into a steel barrel extension, which is bolted and pinned into the aluminum receiver. Bolt-heads are changeable, and the headspace is set between the Barrel extension and the barrel.

The 338 Lapua, 6.5PRC and 300 PRC are available in the Impulse Elite Precision Models, which use an MDT ACC Adjustable Core Competition chassis.

The 300 WSM is available in the Impulse Big Game Models.

Savage has a very strong action with the capability of changing cartridges with different barrel, extension and bolt-head trios. Headspace could remain preset for each trio.