I have begun construction of my new space station. It is a 9.53 Saturn. Remington 700 Action, PTG Lapua Bolt with M16 extractor, Wyatt magazine box. The action, bolt, bolt shroud, trigger guard, floor plate, cocking piece, bolt stop, base, and rings have all been hardchromed. The missile silo is a 30" McGowan Stainless .375 cal. 1-10 twist. The Brake is a Badger Ordnance FTE. It will hopefully launch the pictured 330 grain cutting edge spaceships. Each space ship contains an unhatched gremlin that has been genetically engineered to FUBAR anything it contacts. Two of the space ships are pictured: one already has its solid fuel engine attached, the second one is next to a 22-250 round for comparison. All of the parts are with my gunsmith now. Once it is done I will post more pictures. I will also post my load development results. I am hoping to run the 330s at around 3000 fps. Wish me luck!
- Thread starter 2G5MK
- Start date
Looks badass! Can that case really propel that big bullet to 3k fps?
Tyler:
The honest answer is that I don't know. Lazzeroni publishes just shy of 2900 fps in a 26" Barrel with 350 SMK's. The case is essentially a volumetric sibling to the 378 Weatherby and the 375 A-Square. Most of the data I have seen for those two rounds have 300 grain bullets doing around 3000 fps out of 26" barrels. However, those are maximum loads. I have an older Hodgdon manual that has data for 350 grain bullets in 378 Weatherby. The maximum loads in that manual send 350's out of a 26" tube at 2750. I have also seen some 9.53 Saturn load data on Accuratereloading.com that list a 300 grain barnes x bullet at 3142 fps. So, I hope I can get it going close to 3k, but I will gladly give up 100 fps or more if means I get sub 1/2 MOA groups.
By the way what did you shoot that poor deer in the head with, an M79 grenade launcher?
The honest answer is that I don't know. Lazzeroni publishes just shy of 2900 fps in a 26" Barrel with 350 SMK's. The case is essentially a volumetric sibling to the 378 Weatherby and the 375 A-Square. Most of the data I have seen for those two rounds have 300 grain bullets doing around 3000 fps out of 26" barrels. However, those are maximum loads. I have an older Hodgdon manual that has data for 350 grain bullets in 378 Weatherby. The maximum loads in that manual send 350's out of a 26" tube at 2750. I have also seen some 9.53 Saturn load data on Accuratereloading.com that list a 300 grain barnes x bullet at 3142 fps. So, I hope I can get it going close to 3k, but I will gladly give up 100 fps or more if means I get sub 1/2 MOA groups.
By the way what did you shoot that poor deer in the head with, an M79 grenade launcher?
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It is a big bullet. According to CEB it has a BC of .850. If all goes well, I should be carrying a ton of energy out past 1400 yards.
I believe the correct term is "Metric Ass-Ton"
Just spoke with my gunsmith today. He told me he would have the rifle ready this weekend. I have loaded up a ladder test of 15 rounds starting at 99.5 grains of H4831SC and ending at 106.5 grains. Can wait to head to the range with the new rifle. As soon as it is done I will post pictures of the rifle.
That is a lot of bolt thrust for a standard plain jane 700 LA. I hope the action holds up. Never heard of anyone building a .375 on a 700. With a 300 grn Scenar @ 2800 fps out of the Lapua, your safety factor is getting close to 1.1-1.2. With a 330 grain projo and increased case capacity that number is going drop well below 1.0. The 700 was never designed to take those kinds of stresses from that size of a cartridge. I would not want to be in the shooters position if that combo were to have a catastrophic failure and the thread tennon were to crack or worse yet the lug seats were to fail after repeated firings. Best of luck...
-VB
-VB
Vonbalkenbush
Tell me more. The 700 LA is currently manufactured in 375 RUM. Most of the ballistic data currently published has the 378 Weatherby mag, and 375 Rum in a virtual dead heat in terms of velocity with for example 300 grain bullets. Both with 26' barrels are reported to reach around 2950 +/- 25 fps. I do realize however, that the Lazzeroni case is significantly larger in diameter than the RUM case. I know I may indeed be displaying ignorance, but is the bolt thrust going to be significantly greater than that of a 375 RUM? Also, I do not know how a "Safety Factor" is calculated. Could you tell me more about this? It sounds like an engineering term of art. I have no desire to build something that is destined for a catastrophic failure.
Tell me more. The 700 LA is currently manufactured in 375 RUM. Most of the ballistic data currently published has the 378 Weatherby mag, and 375 Rum in a virtual dead heat in terms of velocity with for example 300 grain bullets. Both with 26' barrels are reported to reach around 2950 +/- 25 fps. I do realize however, that the Lazzeroni case is significantly larger in diameter than the RUM case. I know I may indeed be displaying ignorance, but is the bolt thrust going to be significantly greater than that of a 375 RUM? Also, I do not know how a "Safety Factor" is calculated. Could you tell me more about this? It sounds like an engineering term of art. I have no desire to build something that is destined for a catastrophic failure.
Search all the threads related to bolt thust and case heads over .535". Many consider the .338LM to be pushing safety limit on Ø.700" bolts. More powder and more pressure with a bigger bolt face increases the load the bolt lugs see.
Lug load at 63,000 psi:
Ø.380" case head -> 3.57 tons
Ø.484" case head -> 5.75 tons
Ø.550" case head -> 7.48 tons
Ø.580" case head -> 8.32 tons
Safety factor is how "over built" a device is. Exceding the design limitations on receivers can cause your face/head to have a bad day (see Tyler Kemp's avatar).
Factor of safety - Wikipedia, the free encyclopedia
If you don't explore the upper limit of pressure you shouldn't have to worry. If you exceed the design limitations, be sure to video it and put it on the net so everyone can learn from your mistakes.
Just sayin'.
Lug load at 63,000 psi:
Ø.380" case head -> 3.57 tons
Ø.484" case head -> 5.75 tons
Ø.550" case head -> 7.48 tons
Ø.580" case head -> 8.32 tons
Safety factor is how "over built" a device is. Exceding the design limitations on receivers can cause your face/head to have a bad day (see Tyler Kemp's avatar).
Factor of safety - Wikipedia, the free encyclopedia
If you don't explore the upper limit of pressure you shouldn't have to worry. If you exceed the design limitations, be sure to video it and put it on the net so everyone can learn from your mistakes.
Just sayin'.
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Pretty much everything McFred said to a 'T'. The "Safety Factor" of any manufactured machine is absolutely an engineering term. Anything below 2 is considered playing with fire as Murphy's Law can and almost always does cause situations to arise where a machine is stressed beyond original design limitations. If the Safety Factor is too low, as I believe in your case it is, you could easily be eating that bolt for breakfast with the right combination of circumstances arising. With a case head that size, you need an action with a minimum tennon diameter of 1.350" and a bolt diameter of .750". Those numbers will bump your safety factor back up into the 3-5 range depending on how hot your loads are. That is acceptable from an engineering standpoint, as your project stands now, you could not pay me to get behind the trigger on that thing. One overcharged case, overly fouled bore or minor bore obstruction and I'd be very surprised if you survived with the amount of energy being generated at cartridge ignition. That is just a very limited example of what could cause a rise in chamber pressure, there are many others.
-VB
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Yep 375 RUM is a safer choice in a 700.
If you stay with your current planned chambering and do the ladder test then stop on the lowest node and call it good.
So using the values listed by mcfred which appear to be surface area of the bolt face in inches sqaured multiplied by 63,000 psi. I should limit my pressure to 56,600 psi. In that case my lug load would be approximately 7.48 tons. Thanks to everyone who has given me information.
Damn, might as well be seating the bullet right in a 1lb jug of powder ;-)
After reading numerous threads regarding Remington 700's and Larger bolt faces. I have put the project on hold. I am in the process of acquiring a TAC 338, and selling my 700 action. I did not commence this project so that I would have to limit myself to the lower end of the pressure range for this round. That is not to say that I won't ultimately be happy in the lower pressure ranges. The problem is that I would be afraid to complete a proper ladder test.
I know that BAT will not even do 338 face on their B/MB actions as it is not safe. So putting a CT face on there is just asking for trouble. The lugs on my BAT M and Lawton 8000 are about twice as high and twice as long, really big lugs. I think you are doing the smart thing in the long run.
Have fun!!!
Have fun!!!
Well I'm not too technical, and never really thought about how an action could simply fail from large cartridges being fired but I suppose thats why they make bigger, beefier actions for 338's, etc.
I was looking forward to seeing the results but it is probably a good idea you're looking for a new action to be safe. I guess we'll all need to wait a bit longer to see the new outcome.
Goodluck.
I was looking forward to seeing the results but it is probably a good idea you're looking for a new action to be safe. I guess we'll all need to wait a bit longer to see the new outcome.
Goodluck.
Good things come to those who wait. But it a PITA 
The project will definitely continue. And as promised I will post my results. I am just risk averse. I do not want to hurt myself or anyone else on the line when I am firing. Truth be told I think there is a chance that things would work out fine with my Remington Action. The problem is I don't like to take chances in the safety department. I want to be able to explore the full potential of the cartridge, and after reading a number of comments, I don't mind waiting and spending a little more to have peace of mind. I want to have fun. I don't want to be the first PTG unicorn.
I'm glad to see others are just as concerned as I when I opened this thread.
I don't like the 338LM case heads in a Remington action or anything that's 1" lug x 0.7" bolt body dual lug configuration. Some studies I did on those sizes showed the axial deflection during standard operating pressure loads for a 338LM were 3x's higher on a Remington action than a TRG42 action.
The Stiller TAC338 action isn't "that much" bigger, personally I'd be holding off to get a CheyTac sized action like the Barnard P-Chey. I'm not a big fan of running anything pressure vessel related under a safety margin of 1.0 (MS = Factor of Safety -1) and in something like the vault door holding back 65ksi of plasma-hot gasses... 2 sounds much nicer to me (effective FS = 3.0) for both safety and deflection reasons.
Cool project, I like things like this (even though I don't have space to shoot them enough to justify it) but the last thing I'd like to hear about is someone experimenting and catching a bolt through the noggin. Saw that once a couple years ago, dude foolishly overloaded a 6mm Lee Navy and killed himself.
I don't like the 338LM case heads in a Remington action or anything that's 1" lug x 0.7" bolt body dual lug configuration. Some studies I did on those sizes showed the axial deflection during standard operating pressure loads for a 338LM were 3x's higher on a Remington action than a TRG42 action.
The Stiller TAC338 action isn't "that much" bigger, personally I'd be holding off to get a CheyTac sized action like the Barnard P-Chey. I'm not a big fan of running anything pressure vessel related under a safety margin of 1.0 (MS = Factor of Safety -1) and in something like the vault door holding back 65ksi of plasma-hot gasses... 2 sounds much nicer to me (effective FS = 3.0) for both safety and deflection reasons.
Cool project, I like things like this (even though I don't have space to shoot them enough to justify it) but the last thing I'd like to hear about is someone experimenting and catching a bolt through the noggin. Saw that once a couple years ago, dude foolishly overloaded a 6mm Lee Navy and killed himself.
That's pretty cool. But if you want to go big..... go for a 510 Battleship! 416 Rigby brass cut down for 50 BMG bullets. We use Lehigh controlled fracturing rounds with a 95gr 6mm bullet stuck into it which turns them into "Controlled Fracturing Payloads"
They are subsonic but I would not want to be on the receiving end of one. At 400 yards this will still hit harder then a 44 magnum point blank!
This stuff is to much fun! Anyone seen those new 185gr projectiles for the 338LM? They are said to hit 4k fps easily..... talk about a varmint hunter!
They are subsonic but I would not want to be on the receiving end of one. At 400 yards this will still hit harder then a 44 magnum point blank!
This stuff is to much fun! Anyone seen those new 185gr projectiles for the 338LM? They are said to hit 4k fps easily..... talk about a varmint hunter!
Just acquired a Stiller TAC 338. Can't wait for it to arrive.
So
after speaking with a number of folks including Mr. Lazzeroni, I finished the gun with my Remington action. No issues whatsoever. 330gr CEB bullet at 3030 FPS. No pressure issues whatsoever. Using H4831 and 215M primers.
7 years... wow! And I whine about waiting for a Form 4.
Pictures are needed!
Pictures are needed!
The only powder I have worked with so far is H4831. The only primers I have used have been Federal 215M. I have tried three bullets so far: CEB MTH 330, CEB MTH 350, and CEB Lazer 350. Both of the 350’s showed potential. However they were extremely long. The 330 seemed to shoot the best. They are also quite long. My best load with them is 215M primer, 103.0 grains of H4831 with a cartridge OAL of 3.980. It is running around 3000 fps. I am trying a new bullet, Hammer Hunter 329 next week. I am also trying RL26. I will post results once I get some.
Ladder Test this Mornining:
Case: Lazzeroni
Primer: 215M
Powder: RL26
Bullet: Hammer Hunter 329g
COAL: 3.850”
Ladder Test: 98.0 - 103.0g in .5g increments
98.0 - 2867 fps
98.5. - 2848
99.0 - 2844
99.5. - 2871
100.0 - 2887
100.5 - 2897
101.0 - 2923
101.5 - 2930
102.0 - 2882
102.5 - 2965
103.0 - Not captured
bottom six shots on picture were shots 1-6, and top 5 were shots 7-11. Range was 110 yards. I usually do ladder tests at 320, but it was really windy this morning.
Case: Lazzeroni
Primer: 215M
Powder: RL26
Bullet: Hammer Hunter 329g
COAL: 3.850”
Ladder Test: 98.0 - 103.0g in .5g increments
98.0 - 2867 fps
98.5. - 2848
99.0 - 2844
99.5. - 2871
100.0 - 2887
100.5 - 2897
101.0 - 2923
101.5 - 2930
102.0 - 2882
102.5 - 2965
103.0 - Not captured
bottom six shots on picture were shots 1-6, and top 5 were shots 7-11. Range was 110 yards. I usually do ladder tests at 320, but it was really windy this morning.
Attachments
I spoke with John Lazzeroni. I also reviewed a number of posts by Kirby Allen. Both of them have used Remington 700 actions in the past for their cartridges.
