37XC vs 375 ct

jasent

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37XC .vs 375cheytac
What are some pro’s and con’s. I’ve been planning my next build and was thinking 375 ct
Friends recommended 37XC
My next personal goal is 2500-3000 range
Which way would you go in my shoes? And why
 
375XC sounds great if you already have something like an AXMC or DT in 338LM and can just add the barrel and be in the ELR game. Downside is single feed and less velocity

375CT requires a bigger action but offers more velocity and can be magazine fed. Personally I'm dying to get into a Cadex 375CT but just can't justify it.
 
I just got my 375CT its a Cadex Shadow 32in 1-7 twist and will be shooting 377CE to start as i have 250 of them then i will move up to the 402 CE's. Going to the range in the morning to break it in. I have shot my .338 LM out to 2616 yards so looking to go over 3000 with the 375 CT
 
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BLUF: 375 CT or 375 CT improve based on performance pass 2,500 yards with 377 gr and 402 gr Cutting Edge MTAC.

Depending on your budget...375 AM or 458 Maximus. APS by Kirby Allen.

Cadex Chassis (Mag 4.725") and Cadex/JJ Rock Co Action. Beefier bolt to handle the cartridge. Barrel 7-8T, length 32".

If budget is a limit, the 375 CT.

Good luck with the build!
 
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Hi,

I think it would really depend on if rifle overall weight was something you were really trying to keep fairly light.
It is not big secret that David used a rifle weight as part of his development process of the 33/37XC. His preference is 25lb and under based from the cash prize he is offering at KO2M based on someone winning with rifle that meets that weight limit.

IF you want 338LM sized weapon system then the 33/37XC.
IF you do not mind stepping up a size on weapon system then the 375CT.

IF you want 33/37XC in repeater form then you are going to build that on a CT sized receiver (With changed boltface of course) anyways :)

I do not have a 33/37XC yet so I cannot give direct experience but it appears it is easier to get low single digit MV deviations with the case design and slightly more optimize powder fill ratio than the CTs.

The larger action build (CT) can always be modified to handle the smaller cartridge but the smaller action build (XC) really cannot be modified to handle the larger cartridge :)

Sincerely,
Theis
 
Even though the OP was concerning the 375XC and 375CT I'm going to mention the 375 Enabler only because of Bryan Litz's comments in his write up about the Enabler. In summary he was stating that the large capacity cartridges were having issues with velocity deviation due to the fouling caused by the larger case capacities. I'm not sure where the 375CT would fall into that category but I assume the 375XC with its lesser case capacity would be right in line with the 375 Enabler...
 
Even though the OP was concerning the 375XC and 375CT I'm going to mention the 375 Enabler only because of Bryan Litz's comments in his write up about the Enabler. In summary he was stating that the large capacity cartridges were having issues with velocity deviation due to the fouling caused by the larger case capacities. I'm not sure where the 375CT would fall into that category but I assume the 375XC with its lesser case capacity would be right in line with the 375 Enabler...
The paper on the Enabler is loaded with bias so it's far from being a fair and serious analysis (with lots of apple to oranges...) and I love AB claim about the Cheytac not being "magazine feed-able with the longer bullets" WTF???
Having said this, I'm working on a 37XC build (not 375XC :oops: ) and the performance is there. Don't understand why some people claims the 375CT can go faster because most of the comparisons are based on different barrel length. 37XC case is longer than 375CT which at least should put them on the same velocity potential at the SAME barrel lenght.
 
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Weight is not really a concern( would like to keep it under 40lbs). Not worried about mag feed but it would be nice option.
Other thing I didn’t mention is I can get: Lawton 8000 action (marked CheyTac m310)
-Jewel JT-09 trigger
-McRee Precision chassis
For $1500 from a friend.
I do not have a Lapua size action currently, but could get a savage 112 target for around 900 new but don’t like the stock or trigger
 

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The paper on the Enabler is loaded with bias so it's far from being a fair and serious analysis (with lots of apple to oranges...) and I love AB claim about the Cheytac not being "magazine feed-able with the longer bullets" WTF???
Having said this, I'm working on a 37XC build (not 375XC :oops: ) and the performance is there. Don't understand why some people claims the 375CT can go faster because most of the comparisons are based on different barrel length. 37XC case is longer than 375CT which at least should put them on the same velocity potential at the SAME barrel lenght.

I've no experience or knowledge to disagree with you in the least. The info on the Enabler is certainly a sales driven informational piece that paints the product in its best light.

I found it interesting and educational that the fouling was driving the velocity deviations. Good info to know going forward for sure.

Are you going to be posting your experience with the 37XC? I would be very interested to see your results, it looks to be a very promising round.
 
I'd do some research before committing but the 37XC does seem like a decent sort with a lot less upfront cost than buying a big enough action for the CT. As for the DT there are guys who do barrels. I built a 33XC for my DT and so far I'm impressed. 31" barrel and I'm getting 3350 out of the 265 Cutting Edge Lazers. Heading out to a shoot next week to see how far we can go. I'm going with a friend who was hitting at 2700 last year with his Desert Tech HTI in 375 Cheytac. We shall see how it goes.
I will say the 33XC brass from Peterson seems to be pretty good. The dies I got from Tubb for the XC can be used for the 33 or 37 by switching bushings and the dies work well. I'm seeing .001" of runout or less so far. I like the idea of being able to use my 338 Lapua action for the longer range 33XC. Love to have the Cheytac but don't want to spend $6K to get started.
Brass for the XC is a little over $2 a case but I'm using the press, shell holder and other equipment I've already got for the 338 Lapua so don't need to buy all that.

You must choose. I'm thinking I might buy a blank for the 37XC and give it a shot in the not too distant future.

Frank
 

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I've no experience or knowledge to disagree with you in the least. The info on the Enabler is certainly a sales driven informational piece that paints the product in its best light.

I found it interesting and educational that the fouling was driving the velocity deviations. Good info to know going forward for sure.

Are you going to be posting your experience with the 37XC? I would be very interested to see your results, it looks to be a very promising round.
Yes sir, will follow on as soon as I get it done.
 
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I'd do some research before committing but the 37XC does seem like a decent sort with a lot less upfront cost than buying a big enough action for the CT. As for the DT there are guys who do barrels. I built a 33XC for my DT and so far I'm impressed. 31" barrel and I'm getting 3350 out of the 265 Cutting Edge Lazers. Heading out to a shoot next week to see how far we can go. I'm going with a friend who was hitting at 2700 last year with his Desert Tech HTI in 375 Cheytac. We shall see how it goes.
I will say the 33XC brass from Peterson seems to be pretty good. The dies I got from Tubb for the XC can be used for the 33 or 37 by switching bushings and the dies work well. I'm seeing .001" of runout or less so far. I like the idea of being able to use my 338 Lapua action for the longer range 33XC. Love to have the Cheytac but don't want to spend $6K to get started.
Brass for the XC is a little over $2 a case but I'm using the press, shell holder and other equipment I've already got for the 338 Lapua so don't need to buy all that.

You must choose. I'm thinking I might buy a blank for the 37XC and give it a shot in the not too distant future.

Frank
I use a regular old rock chucker to load my snipetac. It fits just fine so don’t let that deter you from the bigger round.
 
The reason I went for the snipetac was; 1, I got a good deal on an unbuilt package of parts, and 2, I wanted to run the high Cheytac load at lower pressure. I’ve watched enough of the cheytac guys running the mid 3100s and have to beat their bolt open from time to time that I knew I wanted to avoid that. I don’t know if the xc or enabler has that problem or not.
 
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Just got back from South Dakota and I'm quite happy with the 33XC and pretty impressed with the 375 CT in the HTI. I managed hits out to 2500 with the 33XC in my SRS and my buddy made it to 2600 with my rifle. I was all around the 2700yd target but with the wind changing by the second I couldn't quite get it there. With the same rifle and scope I got out to 2000 with my 7.5 X 55 Swiss barrel in the SRS and not too many rounds to get there. Shooting 308 175gr Tipped Sierra Matchkings at 2880 in the 27" barrel. I was quite pleased and could have gone further if the Charlie Tarac my buddy had would have locked on to my covert handguard. I was one groove short of the lock so no go. Scope was topped out at about 2050 yds with that round. Only got out to 1500yds with the 6.5X47 because we couldn't see the misses in the uncharacteristic green grass. Normally its a bit dustier and drier out there but like much of the US they've had lots of rain and the grass is tall. I think the 6.5 would go a lot further.

Overall I'm really happy and will work on the load development a bit more. Not happy with reloader 33. Its dirty, more temp sensitive than I'd like and the change from lot to lot was more than I've seen in other powders I've used. Looking for some H50BMG, and VV N570 like everyone else. I have a little over a year this time to work things out instead of 2 months. Should be able to get it done. The 265 gr Cutting Edge Lazers were perfect for the task and to my surprise the Strelok Pro phone app worked really well for all 3 cals I shot. 6.5X47, 7.5X55 Swiss and 33XC. Never got a chance to run the 338LM so I've got a couple hundred rounds I can shoot elsewhere.

My buddy made it to 2 miles (3520 yds) with his HTI in 375 Cheytac running the 36" barrel I made up from a Bartlein blank and 400gr Cutting edge Lazers. Very impressive to see rifles shooting that far and watching target indicator lights flashing through a 60 power scope. Love those flashers.....

My opinion based on watching both cals shooting side by side over the last week is that the 33XC is great for those who want to work their way into the ELR sport without shelling out a mint. If you have a 338LM based action its possible to do up a barrel for the XC. You'll likely be stuck single feeding but quite a few do that anyway to keep from dinging bullets and shaking powder around. On the other hand being able to toss the 400gr class bullets at over 3000fps will gain a lot more range for the same scope settings and allow you to go much further out. If that is your aim than the 375 CT is a great choice. I'm not sure what to think about the 37XC yet but I'm thinking I might need a barrel for that one too just to check it out. I can share dies and maybe use some of my 33 brass for startups. Not sure it will get the range advantage the Cheytac has as there just isn't the powder space. It should make it out to 3000 pretty easily though. I had enough left in the scope to go to just over 3000yds with the 33XC using the Nightforce 5-25 ATACR and a 70MOA mount from Defense Solutions. The mount gave me just over 120moa of up while still allowing a 100yd zero with every cal I shoot in the Desert tactical SRS. https://defensesolutionsllc.com/



Frank
 
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Just got back from South Dakota and I'm quite happy with the 33XC and pretty impressed with the 375 CT in the HTI. I managed hits out to 2500 with the 33XC in my SRS and my buddy made it to 2600 with my rifle. I was all around the 2700yd target but with the wind changing by the second I couldn't quite get it there. With the same rifle and scope I got out to 2000 with my 7.5 X 55 Swiss barrel in the SRS and not too many rounds to get there. Shooting 308 175gr Tipped Sierra Matchkings at 2880 in the 27" barrel. I was quite pleased and could have gone further if the Charlie Tarac my buddy had would have locked on to my covert handguard. I was one groove short of the lock so no go. Scope was topped out at about 2050 yds with that round. Only got out to 1500yds with the 6.5X47 because we couldn't see the misses in the uncharacteristic green grass. Normally its a bit dustier and drier out there but like much of the US they've had lots of rain and the grass is tall. I think the 6.5 would go a lot further.

Overall I'm really happy and will work on the load development a bit more. Not happy with reloader 33. Its dirty, more temp sensitive than I'd like and the change from lot to lot was more than I've seen in other powders I've used. Looking for some H50BMG, and VV N570 like everyone else. I have a little over a year this time to work things out instead of 2 months. Should be able to get it done. The 265 gr Cutting Edge Lazers were perfect for the task and to my surprise the Strelok Pro phone app worked really well for all 3 cals I shot. 6.5X47, 7.5X55 Swiss and 33XC. Never got a chance to run the 338LM so I've got a couple hundred rounds I can shoot elsewhere.

My buddy made it to 2 miles (3520 yds) with his HTI in 375 Cheytac running the 36" barrel I made up from a Bartlein blank and 400gr Cutting edge Lazers. Very impressive to see rifles shooting that far and watching target indicator lights flashing through a 60 power scope. Love those flashers.....

My opinion based on watching both cals shooting side by side over the last week is that the 33XC is great for those who want to work their way into the ELR sport without shelling out a mint. If you have a 338LM based action its possible to do up a barrel for the XC. You'll likely be stuck single feeding but quite a few do that anyway to keep from dinging bullets and shaking powder around. On the other hand being able to toss the 400gr class bullets at over 3000fps will gain a lot more range for the same scope settings and allow you to go much further out. If that is your aim than the 375 CT is a great choice. I'm not sure what to think about the 37XC yet but I'm thinking I might need a barrel for that one too just to check it out. I can share dies and maybe use some of my 33 brass for startups. Not sure it will get the range advantage the Cheytac has as there just isn't the powder space. It should make it out to 3000 pretty easily though. I had enough left in the scope to go to just over 3000yds with the 33XC using the Nightforce 5-25 ATACR and a 70MOA mount from Defense Solutions. The mount gave me just over 120moa of up while still allowing a 100yd zero with every cal I shoot in the Desert tactical SRS. https://defensesolutionsllc.com/



Frank
Thank you Frank for that write up

I’ve decided to give the 37 xc a go. Will start a thread on the build and results when I can
 
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Iam really liking the looks of the 37xc. However I think it's going to be a bit short on case capacity to run with the boys.

What do you guys think of putting a .350 neck on it and a 40deg shoulder. Move everything forward.
 
I thought the bigger the bang the better chance you had at hitting your target ?

Hi,

Not necessarily.
If that were the pure truth the BMGs would be ruling the ELR world but ELR world is more about most efficient balance between velocity, projectile mass, internal ballistic optimization, and aerodynamic stability (specifically the transonic and subsonic realms).

Sincerely,
Theis
 
Iam really liking the looks of the 37xc. However I think it's going to be a bit short on case capacity to run with the boys.
What do you guys think of putting a .350 neck on it and a 40deg shoulder. Move everything forward.

Moving the shoulder forward a little won't gain you much. The shoulder is about as flat as you can get it for any gain in capacity. So that means 40 deg won't help much.
Looking at the data posted on tubbs site the XC doesn't look much slower than the Cheytac. My buddy was shooting 350gr Cutting Edge Lazers in his factory barreled HTI at 3050fps and getting out to 2700yds last summer with no problems. My guess is that the XC would be pretty close to that as is. We boosted his range this summer by going from the 29" factory barrel to a 36" barrel so he was running the 400gr Lazers at the same speed as the 350s in last years setup. If you make up a 32 or 34" barrel for your rifle with the XC you should have a pretty good long range shooter that will give the cheytac a run.

Frank
 
Hi,

Not necessarily.
If that were the pure truth the BMGs would be ruling the ELR world but ELR world is more about most efficient balance between velocity, projectile mass, internal ballistic optimization, and aerodynamic stability (specifically the transonic and subsonic realms).

Sincerely,
Theis

Not only that on the way someone will stumble on a bullet caliber that is just tad better than the rest , aerodnamics are not realy scalable 1:1 at some point one size will preform better troughout the regime of ELR shoot. So i expect changes and calibres poping up for a while till someone strikes gold.

AB -Enabler pitch is PR , they are looking at some big bucks contract for the military and using the ELR scene for R&D
 
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Hi,

A thing to remember about the big XCs....they are the size and dimensions they are to keep them usable in Davids rifle design..not to out run the larger cased cartridges.

More along the lines of the "largest" that can fit into a predetermined size hole instead of can it out perform those that fit into larger size holes.

Complete size optimization of a cartridge case that fits into a preexisting weapon system.

Sincerely,
Theis
 
Hi,

A thing to remember about the big XCs....they are the size and dimensions they are to keep them usable in Davids rifle design..not to out run the larger cased cartridges.

More along the lines of the "largest" that can fit into a predetermined size hole instead of can it out perform those that fit into larger size holes.

Complete size optimization of a cartridge case that fits into a preexisting weapon system.

Sincerely,
Theis
Not dissimilar to a 300PRC for normal long actions. Can run damn close to a 300 Norma without bigger action boltface etc etc
 
Hi,

A thing to remember about the big XCs....they are the size and dimensions they are to keep them usable in Davids rifle design..not to out run the larger cased cartridges.

More along the lines of the "largest" that can fit into a predetermined size hole instead of can it out perform those that fit into larger size holes.

Complete size optimization of a cartridge case that fits into a preexisting weapon system.

Sincerely,
Theis

True.

What I like about that family of cartridges though, is that if I ever decide to step up from a .300NM, I can get a barrel spun up in 33XC or 37XC for my existing rifle.

It's a huge cost to build up a whole new gun, especially on the scale of the 375CT/50 BMG actions. For a lot of people like myself, thats going to make the big XC cartridges desirable.

May not be the best ELR cartridge in the world, but it makes ELR type systems a lot more attainable to someone like myself, who probably would not go through the effort and expense of building an even bigger rifle than my .300NM.
 
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I agree. I'm not looking to go bigger than .582 boldface. Kinda thinking of wildcating the 37xc not sure it would be worth the trouble
 
Hi,

A thing to remember about the big XCs....they are the size and dimensions they are to keep them usable in Davids rifle design..not to out run the larger cased cartridges.

More along the lines of the "largest" that can fit into a predetermined size hole instead of can it out perform those that fit into larger size holes.

Complete size optimization of a cartridge case that fits into a preexisting weapon system.

Sincerely,
Theis

The 33 and 37XC makes lots of sense not just for Tubb rifle but for any Lapua Magnum sized action bringing ELR into reach of far more shooters. Its also nice that dies are same for both 33 and 37XC just different bushings.
33XC might seem at a disadvantage but ,if you look at ELR competitions most shooters fail prior to 2000y

I am adding 33XC to my multicaliber rifle that will mostly shot 6.5Creedmoor and .300NM. Not willing to invest in CT sized rifle for limited ELR use.
 
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Not aware specifically but I'm sure the usual OEM barrel providers could do it. Probably start with TS Customs and go from there.

you can go with TS customs if you want to pay 50-100% more on a benchmark blank.

Or, go with ES Tactical. He has made 4 HTI barrels for me and I wager he's the most experienced with HTI. Trust me on this one.
 
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you can go with TS customs if you want to pay 50-100% more on a benchmark blank.

Or, go with ES Tactical. He has made 4 HTI barrels for me and I wager he's the most experienced with HTI. Trust me on this one.

Perhaps I'm missing something, but what is this 50-100% more on a Benchmark blank you are talking about?

Are you saying that he charges 50-100% more than others on Benchmark blanks? Or that the benchmark blanks that he uses cost 50-100% more than what ES Tactical charges for a budget brand blank?

TS Customs does excellent work. He has quick turn around times, spins up some extremely precise barrels, and his prices are within that of his peers. Though I normally drop ship TS Customs barrels, I've used their Benchmark blank for a 6.5 Creedmoor build, and I'm not seeing this 50-100% uplift you are talking about.
 
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Not long ago I was quoted $2400 for a 338 Lapua conversion by Primal Tights. Done by TSC on a benchmark blank. Maybe he’s (Prime Tights) taking the cut. You can get one spun up on a blank of your choice for waaaay less than that.

Go ahead and call ES Tactical and TSC and SAC and tell us how their prices compare.

Always good to shop around. Not everybody is charging the same. Not even close.
 
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Not long ago I was quoted $2400 for a 338 Lapua conversion by Primal Tights. Done by TSC on a benchmark blank. Maybe he’s (Prime Tights) taking the cut. You can get one spun up on a blank of your choice for waaaay less than that.

Go ahead and call ES Tactical and TSC and SAC and tell us how their prices compare.

Always good to shop around. Not everybody is charging the same. Not even close.

That's expensive. Maybe things are different for the DTI rifles, I don't know.

For shouldered barrels for all the standard actions, TS Customs makes a great product, at a fair price and with a quick turnaround time.

I've never dealt with Primal Rights, always directly with TS Customs. No experience with DTI barrels though.