The new 33XC & 37XC cartridges designed by David Tubb

[biffj]

Sooo I just bought a Savage elite precision in 338 lapua, and was planning to rechamber soon with a 37xc, is my action strong enough for the 37xc?

Looking at it from a logic standpoint I can't see any reason your Savage action wouldn't handle it. The max chamber pressure for each is the same and since the 33 and 37XC cases are both based on the 338 Lapua case your area will be the same meaning the bolt thrust should be the same so no extra load on your bolt lugs. Some might even suggest that the extra area of the 37XC case would hold it to the chamber more and reduce bolt thrust but I'd not agree with that.

Frank

 

[BoltActionBrotherhood]

Looking at it from a logic standpoint I can't see any reason your Savage action wouldn't handle it. The max chamber pressure for each is the same and since the 33 and 37XC cases are both based on the 338 Lapua case your area will be the same meaning the bolt thrust should be the same so no extra load on your bolt lugs. Some might even suggest that the extra area of the 37XC case would hold it to the chamber more and reduce bolt thrust but I'd not agree with that.

Frank

SOOOOO now the question is, will the 41xc work lol?

 

[7mmShooter]

SOOOOO now the question is, will the 41xc work lol?

Yes, less stress with the bigger bore diameter

 

[Bmitchell448]

Not yet...still enjoying the 338 LM.

Ok, ive been looking to see who can spin one up for the AXMC.

 

[Nik H]

Ok, ive been looking to see who can spin one up for the AXMC.

I think that has been discussed somewhere before. I would assume that there are a few people who could spin one up. I was going to stick with @Robert Gradous or at least see if he could spin up a 33XC for the AXMC. He did my AT 6.5 M24 profile last year and it is a fabulous barrel

 

[Bmitchell448]

I think that has been discussed somewhere before. I would assume that there are a few people who could spin one up. I was going to stick with @Robert Gradous or at least see if he could spin up a 33XC for the AXMC. He did my AT 6.5 M24 profile last year and it is a fabulous barrel

Thanks, Ill reach out and see what he says.

 

[hypertex]

PM Gixxer2000, he may have an AI 33XC barrel for sale. I don't know which AI though, he has a few different models.

It is for an AXMC

 

[joemusso]

Where are you guys sourcing your barrels at?
Im looking for 34" straight and cant find one.

 

[Bravo6niner]

Where are you guys sourcing your barrels at?
Im looking for 34" straight and cant find one.

K&P barrels or Schneider are a couple. Both usually are pretty quick. K&P got me a barrel in two weeks.

 

[biffj]

I got a Schneider for my 33XC and it took about 4 weeks. Much faster than most I normally deal with and its a nice piece. I'd buy more blanks from them now that I know they exist. Very helpful folks.

Frank

 

[badassgunworks]

Ks barrels in canada super quality super price and 2 to 3 weeks turn around time

 

[camotoe]

any news on the 390 atips, anybody run them yet

 

[joemusso]

Thank you for the recommendation on a barrel maker. K&P barrels is the one I'm going with.
I'm looking at the 1.8 twist 1.250 straight 35" with 34" finish length. 33XC is the cartridge I want to go with
Which would you go with SS or CM

Thank you all for your input.

 

[jasent]

Cm seems to last a hair longer imo but SS is much easier to care for

 

[biffj]

If you're running a suppressor, which I think everyone should.....stainless is a better choice. The suppressor traps a lot of the water vapor in the powder gas and if you don't pull the can every time you shoot and oil the bore you can get corrosion and pitting. Stainless will be more resistant to that. As for wear the jury seems to be out. Some makers say the CM will be a little more accurate longer and others say the opposite. I've been running stainless for years because I make suppressors and pitted bores are a pain.

Frank

 

[PTPATAW]

Anyone have any results with the 300gn A-Tips?

 

[pinhead]

I contacted Silencerco a few weeks back and they said I can use my Hybrid 46 can on my 36” 37XC with no issue. I’m in the slow process of collecting components for it so it’s unfired but hopefully that will change this spring.

 

[waveslayer]

Are

I contacted Silencerco a few weeks back and they said I can use my Hybrid 46 can on my 36” 37XC with no issue. I’m in the slow process of collecting components for it so it’s unfired but hopefully that will change this spring.

You running it out of your DT?

 

[pinhead]

Yes, and it’s still balancing toward the rear of the rifle.
22” 6 Creed + brake sits next to it for reference.

 

[waveslayer]

Yes, and it’s still balancing toward the rear of the rifle.
22” 6 Creed + brake sits next to it for reference.

View attachment 7533471

Looks so sick! That out of the SRS? Looks like I need a new conversion kit!

 

[pinhead]

Yes sir, that’s the standard Desert Tech SRS A1 Covert with a 36” 37XC barrel and .585” bolt.

 

[kthomas]

Correct the defiance .750 bolt have 700 lugs and tenon . Makes no sense to me .

So I'm assuming my .585 bolt face, 0.750 OD bolt body Defiance would not be considered a good candidate for the 33XC...

 

[badassgunworks]

So I'm assuming my .585 bolt face, 0.750 OD bolt body Defiance would not be considered a good candidate for the 33XC...

Not the best option but it will work. Will show signs of pressure early. Even more so then the .700 bolt body from defiance. better off going with a larger a tion with a larger action body and larger. Tennon 1.125 minmum

 

[JB.IC]

Not the best option but it will work. Will show signs of pressure early. Even more so then the .700 bolt body from defiance. better off going with a larger a tion with a larger action body and larger. Tennon 1.125 minmum

im building an 33XC off an AI AXSR. Do you for see any issues with that?

 

[kthomas]

Not the best option but it will work. Will show signs of pressure early. Even more so then the .700 bolt body from defiance. better off going with a larger a tion with a larger action body and larger. Tennon 1.125 minmum

Interesting. I wonder if this is why I am seeing pressure signs early compared to others with my .300NM...

 

[Tjfarmer]

Yes sir, that’s the standard Desert Tech SRS A1 Covert with a 36” 37XC barrel and .585” bolt.

who did your barrel work? looking at options on a xc platform, like the idea of a long barrel without having a 6ft gun....looks like the a1 and a2 are nice platforms,triggers, etc... plenty of strength in the action, etc.I take it?

 

[pinhead]

ES Tactical. I am working on getting components so it’s unfired to date.

 

[Backspace]

Getting ready to chamber a 33XC. Where is a good source for load data? I read through Tubbs' reports and just hoping to find a little more information. I've got h50bmg, VV 20N29, imr 8133, and a couple pounds of RL33. Planning to run 300 hybrids. Hoping a 8.5 twist isn't too fast for the jackets on the bergers.

 

[biffj]

8.5 twist is probably a little fast for the jacketed stuff if you're going to run them fast. Otherwise you should be fine. I never ran anything but solids through mine and had no issues but a customer saw a lot of grey puffs when he ran jacketed through his rifle. Not every bullet blew but a decent percentage did.

I tried some of the 300s but ended up running Cutting Edge 265's. The difference in velocity made up for the weight when the range was long. I ran RL33 for the most part but tried some of the others. I didn't try any of the VV stuff because I couldn't find it. Might be the ticket. Also looked at RL50 but didn't get a chance to work up much for loads.

Frank

 

[Backspace]

8.5 twist is probably a little fast for the jacketed stuff if you're going to run them fast. Otherwise you should be fine. I never ran anything but solids through mine and had no issues but a customer saw a lot of grey puffs when he ran jacketed through his rifle. Not every bullet blew but a decent percentage did.

I tried some of the 300s but ended up running Cutting Edge 265's. The difference in velocity made up for the weight when the range was long. I ran RL33 for the most part but tried some of the others. I didn't try any of the VV stuff because I couldn't find it. Might be the ticket. Also looked at RL50 but didn't get a chance to work up much for loads.

Frank

Yea, thought the 8.5 was probably too fast. Got too good of a deal on it to pass though. It is a 36" blank and i planned on finishing it pretty long, so it sounds like i might want to start sourcing some solids.

 

[biffj]

Lots of guys like the Warners and I've had great results with the Cutting Edge stuff too. Good places to start at least.

Frank

 

[Dave62677]

Check out badlands precision , they have some really high BC solid

 

[Raven81]

Waiting on a 30” Carbon6 33XC from StraightJacket for my AXMC. Have dies, brass, and 300 OTMs. But only powder I could find was Vihtavouri V20N29. Has anyone tried this powder as a H50BMG substitute in 33XC?

 

[BCX]

Not the best option but it will work. Will show signs of pressure early. Even more so then the .700 bolt body from defiance. better off going with a larger a tion with a larger action body and larger. Tennon 1.125 minmum

I had a similar experience w a Defiance Deviant vs a Surgeon XL w the 338 LM AI. I won't get into details but i believe a XL action is needed w anything over the 300 NM.

 

[MACHTECH]

This is @lethalsquirts making multiple impacts at 2 miles with my 33xc in the AI AXSR. I load 123 grains of H50BMG w/ Berger 300 otm's seated at the lands. You can also use Retumbo or N570 successfully, but I found the best accuracy/velocity using H50BMG. I couldn't sell my .375 cheytac fast enough after returning home from this trip to Kansas. At 2 miles, my elevation was just over 10 mils less than that of the cheytac.

 

[BCX]

NOT A AI OWNER, Curious on what the AI action and bolt diameter is on the .590 BF?

 

[Steel head]

NOT A AI OWNER, Curious on what the AI action and bolt diameter is on the .590 BF?

Don’t know but it has a stout barrel tenon.

 

[BCX]

Action body has to be 1.450? Searching it now.

 

[MACHTECH]

Waiting on a 30” Carbon6 33XC from StraightJacket for my AXMC. Have dies, brass, and 300 OTMs. But only powder I could find was Vihtavouri V20N29. Has anyone tried this powder as a H50BMG substitute in 33XC?

20N29 is going to be too slow burning IMO. Sorry

 

[Steel head]

Action body has to be 1.450? Searching it now.

With a tenon like this it’s definitely not small

 

[Geno C.]

This is @lethalsquirts making multiple impacts at 2 miles with my 33xc in the AI AXSR. I load 123 grains of H50BMG w/ Berger 300 otm's seated at the lands. You can also use Retumbo or N570 successfully, but I found the best accuracy/velocity using H50BMG. I couldn't sell my .375 cheytac fast enough after returning home from this trip to Kansas. At 2 miles, my elevation was just over 10 mils less than that of the cheytac.
View attachment 7549325

Just imagine if you were shooting a good bullet!

 

[Geno C.]

8.5 twist is probably a little fast for the jacketed stuff if you're going to run them fast. Otherwise you should be fine. I never ran anything but solids through mine and had no issues but a customer saw a lot of grey puffs when he ran jacketed through his rifle. Not every bullet blew but a decent percentage did.

I tried some of the 300s but ended up running Cutting Edge 265's. The difference in velocity made up for the weight when the range was long. I ran RL33 for the most part but tried some of the others. I didn't try any of the VV stuff because I couldn't find it. Might be the ticket. Also looked at RL50 but didn't get a chance to work up much for loads.

Frank

I’ve run 300 Bergers out of my 338 out of an 8 twist and they didn’t blow up

 

[Steel head]

I’ve run 300 Bergers out of my 338 out of an 8 twist and they didn’t blow up

That’s good new to me!

 

[Geno C.]

There are better bullets out there though

 

[Steel head]

There are better bullets out there though

On order

 

[Geno C.]

You’re going to like the badlands

 

[Tjfarmer]

ES Tactical. I am working on getting components so it’s unfired to date.

How long was ES Tactical before ya got it. Seems I talk to one guy and it’s 6-8weeks, next guy is 15weeks...

 

[biffj]

I’ve run 300 Bergers out of my 338 out of an 8 twist and they didn’t blow up

I've run them out of my 338 too but I wasn't getting 3200 fps out of the 338. The faster the bullets go the faster they spin. Thats where the trouble comes in with jacketed stuff vs solids and fast twist barrels. Keep the velocity down and they won't come apart. Run them too fast and they may blow.

Frank

 

[Geno C.]

3350fps enough for you?

 

[biffj]

Yep, sounds like you're doing ok. Your mileage may vary but if you're getting that velocity out of your 338 without blowing things up you are the master.

Frank
(sorry, I don't ever do emojis but this is intended in a humorous way)