MDWS GPC (General Purpose Cartridge) Family General Info - Page 2

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[ARCHIVED THREAD] - MDWS GPC (General Purpose Cartridge) Family General Info (Page 2 of 3)

Posted: 1/7/2019 7:57:45 PM EDT

[#1]

You should give higher priority to the 30GPC over the 28 in my opinion. 30 cal is so popular in any form, it just makes sense.

Posted: 1/7/2019 8:08:19 PM EDT

[#2]

Quote History

Quoted:
You should give higher priority to the 30GPC over the 28 in my opinion. 30 cal is so popular in any form, it just makes sense.

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It wasn't so much about popularity, it's a process of which prints we had done first, which test blanks and reamers came first, which ones we decided to revise, and then which ones we get the new tooling and blanks for in again first. Just so happens it ended up on this order.

Posted: 1/7/2019 9:41:46 PM EDT

[#3]

Thanks for doing the giveaway the 27 & 24 look very interesting considering I have a ton of various pills for each and quite a bit of 6.8 brass

Posted: 1/8/2019 2:54:27 AM EDT

[#4]

I got one of those special Sulzer Arms receiver sets that uses the Magpul 6.8 mags made for LWRC. I just got notification it shipped.
As soon as the 25 GPC releases, it will have a home in this receiver set!

Then the 22GPC will go into a remington build since i happened to catch a custom 6.8 bolt in the EE section. Just need an action to pair it with!

Love it when gun plans work out, all thanks to MDWS and their gun geniuses! ??

Posted: 1/8/2019 11:47:47 AM EDT

[#5]

I know it’s not in this family of cartridges but what’s the ETA on 30 sabercat barrels and bolts.

Posted: 1/8/2019 11:53:09 AM EDT

[#6]

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Quoted:
I know it’s not in this family of cartridges but what’s the ETA on 30 sabercat barrels and bolts.

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the fat cat line of cats will be back in stock in the spring, waiting on a batch of bolts.

Posted: 1/14/2019 10:42:37 PM EDT

[#7]

OP getting updated with these photos.

Posted: 1/17/2019 5:23:53 PM EDT

[#8]

Starline brass officially on order.

It will have the *-* across the top for Starline, than MDWS GPC along the bottom.

The brass will be in 27 GPC configuration as it is the parent case for all the other GPC cartridges in the family. So, no mater which one you go with there will be factory brass that just needs to be resized and trimmed to the specific member of the family.

Posted: 1/18/2019 1:41:38 AM EDT

[#9]

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Stupid question time!!!!!

What COAL is the 6.8 at in the photos? I *think* I am loading my 6.8 to 2.280 which is my mags length.

All your rounds look a good bit longer then the 6.8.

Also, I can't wait to order something from you guys. I just don't know what it will be yet!

Posted: 1/18/2019 1:42:53 AM EDT

[#10]

Quote History

Quoted:

Stupid question time!!!!!

What COAL is the 6.8 at in the photos? I *think* I am loading my 6.8 to 2.280 which is my mags length.

All your rounds look a good bit longer then the 6.8.

Also, I can't wait to order something from you guys. I just don't know what it will be yet!

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nice catch they are loaded to 2.375 oal

Posted: 2/12/2019 6:46:42 AM EDT

[#11]

Very curious to know how the 24 GPC is expected to perform out of 16" barrels when loaded to the 2.38-2.39" of the new MDWS / Six8 metal mag.

Especially how it would perform with the Cutting Edge 88gr MTH, which expands down to 1600fps and has a .445 G1 BC.

https://cuttingedgebullets.com/243-6mm-88gr-mth-match-tactical-hunting

Bullet length is 1.036", with a projection length of .655".

Posted: 2/12/2019 9:52:44 AM EDT

[#12]

Quote History

Quoted:
Very curious to know how the 24 GPC is expected to perform out of 16" barrels when loaded to the 2.38-2.39" of the new MDWS / Six8 metal mag.

Especially how it would perform with the Cutting Edge 88gr MTH, which expands down to 1600fps and has a .445 G1 BC.

https://cuttingedgebullets.com/243-6mm-88gr-mth-match-tactical-hunting

Bullet length is 1.036", with a projection length of .655".

View Quote

Until we are able to run it through the system I can only speculate that it would be around 2800fps from a 16", using some numbers on otheri bullets we ran through. Will try to get a more accurate prediction for you.

Posted: 2/12/2019 10:04:17 AM EDT

[#13]

Quote History

Quoted:
Very curious to know how the 24 GPC is expected to perform out of 16" barrels when loaded to the 2.38-2.39" of the new MDWS / Six8 metal mag.

Especially how it would perform with the Cutting Edge 88gr MTH, which expands down to 1600fps and has a .445 G1 BC.

https://cuttingedgebullets.com/243-6mm-88gr-mth-match-tactical-hunting

Bullet length is 1.036", with a projection length of .655".

View Quote

here are estimates for the 88 CEB from a 16 on top and a 24 on bottom

Posted: 2/12/2019 10:08:26 PM EDT

[#14]

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Quoted:

here are estimates for the 88 CEB from a 16 on top and a 24 on bottom

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Wonderful, thank you for running those numbers.

Running the numbers through a ballistics calculator, that cartridge + bullet combo will be hard to beat:

6mm 88gr 0.445 G1 BC @ 2750fps = 1600fps expansion range / 500 ft/lbs @ 650 yards.

Posted: 2/12/2019 10:24:45 PM EDT

[#15]

What type of performance can we expect from the 26 GPC with 123gr projectiles out of a 16" barrel when loaded to the same 2.38"?

For example, the 123gr Lapua Scenar?

Posted: 2/12/2019 10:41:31 PM EDT

[#16]

Quote History

Quoted:
What type of performance can we expect from the 26 GPC with 123gr projectiles out of a 16" barrel when loaded to the same 2.38"?

For example, the 123gr Lapua Scenar?

View Quote

the 16 nuders it but here is 16 then 24 with the 123 scenar

Posted: 2/12/2019 11:53:30 PM EDT

[#17]

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Quoted:

the 16 nuders it but here is 16 then 24 with the 123 scenar

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Awesome, thank you for that.

That is a bit hotter then 6.5 grendel, but not super compelling.

I think the 6mm / 24 GPC is where this is likely to really shine in terms of the "AR12" intermediate weapon between the 5.56 AR15 and 6.5 Creedmoor AR10. The 6mm bullets have good BC's, while remaining light enough to get a good velocity out of a 16" barrel with the 6.8 powder charge.

If I may impose one more time, could you run the QL for the 24 GPC 16" 2.38" with the Berger 95gr?
http://bergerbullets.com/product/6-mm-95-gr-vld-hunting/

Posted: 2/13/2019 12:06:06 AM EDT

[#18]

Quote History

Quoted:

Awesome, thank you for that.

That is a bit hotter then 6.5 grendel, but not super compelling.

I think the 6mm / 24 GPC is where this is likely to really shine in terms of the "AR12" intermediate weapon between the 5.56 AR15 and 6.5 Creedmoor AR10. The 6mm bullets have good BC's, while remaining light enough to get a good velocity out of a 16" barrel with the 6.8 powder charge.

If I may impose one more time, could you run the QL for the 24 GPC 16" 2.38" with the Berger 95gr?
http://bergerbullets.com/product/6-mm-95-gr-vld-hunting/

View Quote

16 and 24 with the 95 vld hunter

Posted: 2/13/2019 1:17:56 AM EDT

[#19]

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Quoted:

16 and 24 with the 95 vld hunter

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Awesome, thank you.

Bergers have an 1800fps expansion minimum.

24 GPC 95gr 0.467 G1 @ 2660fps = 1800fps / 681 ftlbs @ 500 yards

I think this, and the 88gr Cutting Edge, have a lot of promise.

Posted: 2/22/2019 2:51:46 PM EDT

[#20]

I was just looking at .264 projectiles, and I was really surprised by how high the BC is on the 108gr Lapua is .467. That seems like it would be a good mix of velocity and bc out of shorter barrels.

What would the velocity be for the 26 GPC with the 108gr out of a 16" barrel when loaded to 2.38?

Posted: 2/22/2019 3:52:53 PM EDT

[#21]

Quote History

Quoted:
I was just looking at .264 projectiles, and I was really surprised by how high the BC is on the 108gr Lapua is .467. That seems like it would be a good mix of velocity and bc out of shorter barrels.

What would the velocity be for the 26 GPC with the 108gr out of a 16" barrel when loaded to 2.38?

View Quote

Sorry BIGGDAWG is out of the office for a while... so is our access to Quickload until he gets back!

hat is a very promising bullet though, agreed.

Posted: 2/22/2019 11:24:44 PM EDT

[#22]

Lol, call me a stick in the mud but like 10 different cartridges is more of a case of special purposes than general purpose.

Posted: 2/22/2019 11:39:52 PM EDT

[#23]

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Quoted:
Lol, call me a stick in the mud but like 10 different cartridges is more of a case of special purposes than general purpose.

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I understand what you're saying.

For us it was more about the parent case/cartridge being the most "General Purpose"... the 27 GPC. If I could only have one it would be the 27. If I had to play multiple specific roles I would use one of the others.

This is my 27 GPC. A 16" and 22" upper for it.

Posted: 2/22/2019 11:59:55 PM EDT

[#24]

Speaking of the 27 GPC, what type of velocity is possible with the 130gr Berger VLD from 2.38" out of a 16" barrel?

Posted: 2/23/2019 8:12:08 AM EDT

[#25]

Quote History

Quoted:
Speaking of the 27 GPC, what type of velocity is possible with the 130gr Berger VLD from 2.38" out of a 16" barrel?

View Quote

We were doing over 2700 from a 24" loaded to 2.35", but didn't keep pushing. Dont have short barrel numbers on that one sorry. It will suffer a bit going from 24-16".

Yamaraja, a member here says he can get to 2800fps from a 22 or 24" with his 6.8SPC... but won't post the load. We used CFE223 and Lever.

Posted: 2/23/2019 2:22:24 PM EDT

[#26]

Quote History

Quoted:
We were doing over 2700 from a 24" loaded to 2.35", but didn't keep pushing. Dont have short barrel numbers on that one sorry. It will suffer a bit going from 24-16".

Yamaraja, a member here says he can get to 2800fps from a 22 or 24" with his 6.8SPC... but won't post the load. We used CFE223 and Lever.

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Quote History

Quoted:

Quoted:
Speaking of the 27 GPC, what type of velocity is possible with the 130gr Berger VLD from 2.38" out of a 16" barrel?

We were doing over 2700 from a 24" loaded to 2.35", but didn't keep pushing. Dont have short barrel numbers on that one sorry. It will suffer a bit going from 24-16".

Yamaraja, a member here says he can get to 2800fps from a 22 or 24" with his 6.8SPC... but won't post the load. We used CFE223 and Lever.

I think for marketing the GPC and AR12/6x/ SixX etc you should focus on the 16" velocities.

A lightweight, 30rd magazine weapon system doesn't really doesn't make sense with a 24" barrel. You loose the weight / bulk advantage of the AR12, and still end up with performance bellow that of a 16" AR10.

One of the big letdowns with the 6.5 Grendel was that all of the velocities that were posted upon its release sounded so good (I think 123gr @ 2650fps was the spec.) Only it turns out that was from 24" barrels that no one was ever going to have. From a 16" barrel that people actually wanted for an AR15 based weapon, the velocity was more in the 2350-2400fps range - essentially a low drag 7.62x39.

Better to undersell and overdeliver velocity wise and use the 16" numbers.

Posted: 2/23/2019 3:59:09 PM EDT

[#27]

Quote History

Quoted:
I think for marketing the GPC and AR12/6x/ SixX etc you should focus on the 16" velocities.

A lightweight, 30rd magazine weapon system doesn't really doesn't make sense with a 24" barrel. You loose the weight / bulk advantage of the AR12, and still end up with performance bellow that of a 16" AR10.

One of the big letdowns with the 6.5 Grendel was that all of the velocities that were posted upon its release sounded so good (I think 123gr @ 2650fps was the spec.) Only it turns out that was from 24" barrels that no one was ever going to have. From a 16" barrel that people actually wanted for an AR15 based weapon, the velocity was more in the 2350-2400fps range - essentially a low drag 7.62x39.

Better to undersell and overdeliver velocity wise and use the 16" numbers.

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Quote History

Quoted:

Quoted:
Speaking of the 27 GPC, what type of velocity is possible with the 130gr Berger VLD from 2.38" out of a 16" barrel?

We were doing over 2700 from a 24" loaded to 2.35", but didn't keep pushing. Dont have short barrel numbers on that one sorry. It will suffer a bit going from 24-16".

Yamaraja, a member here says he can get to 2800fps from a 22 or 24" with his 6.8SPC... but won't post the load. We used CFE223 and Lever.

I think for marketing the GPC and AR12/6x/ SixX etc you should focus on the 16" velocities.

A lightweight, 30rd magazine weapon system doesn't really doesn't make sense with a 24" barrel. You loose the weight / bulk advantage of the AR12, and still end up with performance bellow that of a 16" AR10.

One of the big letdowns with the 6.5 Grendel was that all of the velocities that were posted upon its release sounded so good (I think 123gr @ 2650fps was the spec.) Only it turns out that was from 24" barrels that no one was ever going to have. From a 16" barrel that people actually wanted for an AR15 based weapon, the velocity was more in the 2350-2400fps range - essentially a low drag 7.62x39.

Better to undersell and overdeliver velocity wise and use the 16" numbers.

24" barrels were and still are very common in 6.5 Grendel. There were a lot of 28" originally as well.

20" is also very common, as are 18".

For hunting, in our ongoing game survey, 18" is featured more than any other barrel length, but not such to stick out dramatically. The spread covers 10.5" to 24".

Muzzle velocity is not the be-all, end-all, so when 6.5 Grendel was introduced, almost the entire market of prospective customers were in a mv-centered mindset collectively, not fully understanding the reality of how ballistic coefficient affects energy and performance at distance.

That certainly was true for me in the early 2000s, even though I had been shooting Long Range regularly for 10 years by the year 2005. I was mostly shooting .308 at distance at that time.

I eventually got into .260 Remington because of its growing popularity in LR shooting, as well as doing a bit of .338 LM work with coalition snipers during their training events.

In those days, most people that were using ballistics programs were still using G1 drag models, but the Finns were already using doppler radar data with Quick Target Unlimited.

Berger had a free online program on their site that was very accurate, and I used that for a lot of my dope sheets.

What really surprised me with the effectiveness of BC was shooting my 16" Grendel at 1200yds with the 123gr AMAX.

If you're only looking at muzzle velocity and not BC - even for closer range hunting, you're not getting the important part of the picture for what it is you are trying to do if you care about energy on-target.

Look at a 90gr varmint bullet going really fast at the muzzle, versus a 123gr bullet going 455fps slower at the muzzle and compare them at 100yds.

90gr TNT .281 BC, 2735fps
100yds 2421fps 1171ft-lbs

123gr ELD-M .493 Mach 2 Doppler Band BC, 2280fps
100yds 2116fps 1223ft-lbs

This is what a low-drag 7.62x39 looks like with 123gr Scenar:

Posted: 2/23/2019 4:35:25 PM EDT

[#28]

Quote History

Quoted:
24" barrels were and still are very common in 6.5 Grendel. There were a lot of 28" originally as well.

20" is also very common, as are 18".

For hunting, in our ongoing game survey, 18" is featured more than any other barrel length, but not such to stick out dramatically. The spread covers 10.5" to 24".

Muzzle velocity is not the be-all, end-all, so when 6.5 Grendel was introduced, almost the entire market of prospective customers were in a mv-centered mindset collectively, not fully understanding the reality of how ballistic coefficient affects energy and performance at distance.

If you're only looking at muzzle velocity and not BC - even for closer range hunting, you're not getting the important part of the picture for what it is you are trying to do if you care about energy on-target.

View Quote View All Quotes

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Quote History

Quoted:

Quoted:
Speaking of the 27 GPC, what type of velocity is possible with the 130gr Berger VLD from 2.38" out of a 16" barrel?

We were doing over 2700 from a 24" loaded to 2.35", but didn't keep pushing. Dont have short barrel numbers on that one sorry. It will suffer a bit going from 24-16".

Yamaraja, a member here says he can get to 2800fps from a 22 or 24" with his 6.8SPC... but won't post the load. We used CFE223 and Lever.

I think for marketing the GPC and AR12/6x/ SixX etc you should focus on the 16" velocities.

A lightweight, 30rd magazine weapon system doesn't really doesn't make sense with a 24" barrel. You loose the weight / bulk advantage of the AR12, and still end up with performance bellow that of a 16" AR10.

One of the big letdowns with the 6.5 Grendel was that all of the velocities that were posted upon its release sounded so good (I think 123gr @ 2650fps was the spec.) Only it turns out that was from 24" barrels that no one was ever going to have. From a 16" barrel that people actually wanted for an AR15 based weapon, the velocity was more in the 2350-2400fps range - essentially a low drag 7.62x39.

Better to undersell and overdeliver velocity wise and use the 16" numbers.

24" barrels were and still are very common in 6.5 Grendel. There were a lot of 28" originally as well.

20" is also very common, as are 18".

For hunting, in our ongoing game survey, 18" is featured more than any other barrel length, but not such to stick out dramatically. The spread covers 10.5" to 24".

Muzzle velocity is not the be-all, end-all, so when 6.5 Grendel was introduced, almost the entire market of prospective customers were in a mv-centered mindset collectively, not fully understanding the reality of how ballistic coefficient affects energy and performance at distance.

If you're only looking at muzzle velocity and not BC - even for closer range hunting, you're not getting the important part of the picture for what it is you are trying to do if you care about energy on-target.

I'm well aware of the importance of BC's.

However, velocity retention is more important then energy retention when it comes to the "effective range" of bullets, and comparisons between calibers.

Namely, manufacturers list a "minimum expansion/fragmentation velocity" - not energy - for their bullets. This velocity is anywhere from 2100 fps for a SMK, to 1900fps for a Tipped match king, 1800fps for Berger, to 1600fps for a Cutting Edge Copper, to 1350fps for the Nosler ABLR.

And when it comes to velocity retention, starting velocity is very important. In that way, a lower BC, higher velocity projectile can actually have a longer expansion/fragmentation range.

Using a Berger 1800fps range:

6.5g 16" 130gr VLD 0.562 G1 @ 2350fps = 1800fps expansion @ 400 yards

6mm GPC 16" 95gr VLD 0.467 G1 @ 2660fps = 1800fps expansion @ 500 yards

Likewise, trajectory/ drop is effected quite a bit by starting velocity:

6.5g 16" 130gr VLD 0.562 G1 @ 2350fps = -123" @ 600 yards / -261" @ 800 yards

6mm GPC 16" 95gr VLD 0.467 G1 @ 2660fps = -100" @ 600 yards / -218" @ 800 yards

Posted: 2/24/2019 10:08:01 AM EDT

[#29]

Am I missing something? My old eyes may be skimming across it but I have not seen any mention of reloading dies. What cartridges are available today with dies?

Posted: 2/24/2019 10:16:00 AM EDT

[#30]

Quote History

Quoted:
Am I missing something? My old eyes may be skimming across it but I have not seen any mention of reloading dies. What cartridges are available today with dies?

View Quote

Only the 27 can be purchased today. The 20 is ready and we are making the dies for it and will spin a handful of barrels to put in the store.

Final tooling for all the others is inbound, as well as blanks, and we will be making the first batches of dies.

Blanks are due in the next couple weeks or so, tooling in 3-4 weeks I think at this point.

When we go full production we use Hornady die sets.

Thanks!

Posted: 2/24/2019 10:02:50 PM EDT

[#31]

Have y'all shot the 30?

I would like to see a 16" muzzle velocity table comparing 300bo, 300hamr, 30gpc w/same 125gr & 150gr bullets.

Please no 6.5 grendel replies.

Posted: 2/25/2019 2:57:46 PM EDT

[#32]

Quote History

Quoted:
I was just looking at .264 projectiles, and I was really surprised by how high the BC is on the 108gr Lapua is .467. That seems like it would be a good mix of velocity and bc out of shorter barrels.

What would the velocity be for the 26 GPC with the 108gr out of a 16" barrel when loaded to 2.38?

View Quote

here are estimates for a 16 and 24 inch with the 108 scenar

Posted: 2/25/2019 2:59:00 PM EDT

[#33]

Quote History

Quoted:
Have y'all shot the 30?

I would like to see a 16" muzzle velocity table comparing 300bo, 300hamr, 30gpc w/same 125gr & 150gr bullets.

Please no 6.5 grendel replies.

View Quote

only ones that are shooting now are the 27 and 20 waiting on tooling for the rest.

Posted: 2/26/2019 12:35:33 AM EDT

[#34]

Quote History

Quoted:

here are estimates for a 16 and 24 inch with the 108 scenar

https://www.AR15.Com/media/mediaFiles/261615/108_scenar_16_inch_JPG-857836.jpg

https://www.AR15.Com/media/mediaFiles/261615/108_scenar_24_inch_JPG-857837.jpg

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Awesome, thank you.

Still looks like the 24 GPC 88/95gr has the furthest expansion range / least drop out of 16" barrels.

If real world velocity holds true to the quickload estimates, I think thats going to be the real winner.

Posted: 2/26/2019 3:33:01 PM EDT

[#35]

Quote History

Quoted:
Awesome, thank you.

Still looks like the 24 GPC 88/95gr has the furthest expansion range / least drop out of 16" barrels.

If real world velocity holds true to the quickload estimates, I think thats going to be the real winner.

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Quoted:

Quoted:

here are estimates for a 16 and 24 inch with the 108 scenar

https://www.AR15.Com/media/mediaFiles/261615/108_scenar_16_inch_JPG-857836.jpg

https://www.AR15.Com/media/mediaFiles/261615/108_scenar_24_inch_JPG-857837.jpg

Awesome, thank you.

Still looks like the 24 GPC 88/95gr has the furthest expansion range / least drop out of 16" barrels.

If real world velocity holds true to the quickload estimates, I think thats going to be the real winner.

None of them will compare well to 129gr ABLR in the 6.5 GPC when looking at its expansion threshold of 1300fps.

Same for projectile weight and penetration, in addition to expansion.

None of them will deliver the payload, expansion, and penetration like that bullet does.

Once you start shooting past your PBZ, you're going to apply some type of hold or dial for elevation, so we don't really care about elevation and the differences within intermediate hunting distances are negligible.

Once you start getting past 200-300yds, we care more about wind drift, which is where BC really matters.

129gr ABLR has it all, and kills across the range from close-in to distances that most people will never shoot at, but still has plenty of capability to do so and do it well.

Posted: 2/26/2019 3:42:44 PM EDT

[#36]

NEAT!

Posted: 2/26/2019 9:08:45 PM EDT

[#37]

How would the 20 compare to a .204Ruger? Sorry if I missed it above..

Posted: 2/26/2019 9:29:24 PM EDT

[#38]

Would be interesting to see a TTSX/GMX comparison. Of those less than 1.2", in order of best Litz form factor:

TTSX 100 .264
TTSX 80 .257
TTSX 110 .277
TTSX 100 .257
TTSX 80 .243

Curious which ones retain ~2k impact velocity the farthest. Of those the first two look the most interesting to compare. The 80 quarterbore in particular... out an of ~18" barrel..

Posted: 2/26/2019 9:39:13 PM EDT

[#39]

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Quoted:
How would the 20 compare to a .204Ruger? Sorry if I missed it above..

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fairly close to the 204 i think here is some estimates and there is also some data out there too we are testing it now i just dont' have the data with me on vacation.

Posted: 2/26/2019 11:09:10 PM EDT

[#40]

Quote History

Quoted:
None of them will compare well to 129gr ABLR in the 6.5 GPC when looking at its expansion threshold of 1300fps.

Same for projectile weight and penetration, in addition to expansion.

None of them will deliver the payload, expansion, and penetration like that bullet does.

Once you start shooting past your PBZ, you're going to apply some type of hold or dial for elevation, so we don't really care about elevation and the differences within intermediate hunting distances are negligible.

Once you start getting past 200-300yds, we care more about wind drift, which is where BC really matters.

129gr ABLR has it all, and kills across the range from close-in to distances that most people will never shoot at, but still has plenty of capability to do so and do it well.

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Quoted:

Quoted:

here are estimates for a 16 and 24 inch with the 108 scenar

https://www.AR15.Com/media/mediaFiles/261615/108_scenar_16_inch_JPG-857836.jpg

https://www.AR15.Com/media/mediaFiles/261615/108_scenar_24_inch_JPG-857837.jpg

Awesome, thank you.

Still looks like the 24 GPC 88/95gr has the furthest expansion range / least drop out of 16" barrels.

If real world velocity holds true to the quickload estimates, I think thats going to be the real winner.

None of them will compare well to 129gr ABLR in the 6.5 GPC when looking at its expansion threshold of 1300fps.

Same for projectile weight and penetration, in addition to expansion.

None of them will deliver the payload, expansion, and penetration like that bullet does.

Once you start shooting past your PBZ, you're going to apply some type of hold or dial for elevation, so we don't really care about elevation and the differences within intermediate hunting distances are negligible.

Once you start getting past 200-300yds, we care more about wind drift, which is where BC really matters.

129gr ABLR has it all, and kills across the range from close-in to distances that most people will never shoot at, but still has plenty of capability to do so and do it well.

Yes, the 129 ABLR is really impossible to beat - which also makes it kinda unfair to use as a basis of comparison for cartridges.
Its got a 300fps expansion advantage over any other projectile - and it's not available in .224, 6mm, 6.35, or 6.8 (well, spc weight).

To compare cartridges, they really have to be firing the same brand projectile. Ie 6 vs 6.5mm TMK, 6 vs 6.5 MTH, etc.

Posted: 2/26/2019 11:53:24 PM EDT

[#41]

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fairly close to the 204 i think here is some estimates and there is also some data out there too we are testing it now i just dont' have the data with me on vacation.

https://www.AR15.Com/media/mediaFiles/261615/40_nbt_24_JPG-859356.jpg

https://www.AR15.Com/media/mediaFiles/261615/32_vmax_JPG-859359.jpg

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Thanks. That's very impressive compared to what I'm getting from my .204.

Posted: 3/1/2019 5:17:26 PM EDT

[#42]

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Quoted:
Would be interesting to see a TTSX/GMX comparison. Of those less than 1.2", in order of best Litz form factor:

TTSX 100 .264
TTSX 80 .257
TTSX 110 .277
TTSX 100 .257
TTSX 80 .243

Curious which ones retain ~2k impact velocity the farthest. Of those the first two look the most interesting to compare. The 80 quarterbore in particular... out an of ~18" barrel..

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@Heavy655

so you want quick load predictions for those bullets in the 24, 25, 26 and 27 GPC's ??

we won't have any actual data till the reamers get here on the 24,25 and 26. I will see if i have some data on the 110 ttsx in the 27 GPC

Posted: 3/2/2019 4:03:05 PM EDT

[#43]

Quote History

Quoted:

@Heavy655

so you want quick load predictions for those bullets in the 24, 25, 26 and 27 GPC's ??

we won't have any actual data till the reamers get here on the 24,25 and 26. I will see if i have some data on the 110 ttsx in the 27 GPC

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I thought an apples to apples QL comparison of cartridges using the TTSX would be interesting (mainly because I prefer not splashing lead into my meat). Even if they don't compare well to ABLR or MTH because of the higher expansion velocities. I didn't want you to have to QL every single one, but it would be an interesting way to compare them using similar hunting bullets if you did. So I thought the most interesting ones of the group were the .257 80gr and the .264 100 grain as per Litz form factor numbers. Since they have the most efficient shapes among the TTSX, in theory should retain impact velocity the farthest. And I did mean QL numbers, not real world data.

Posted: 3/3/2019 12:28:21 AM EDT

[#44]

Quote History

Quoted:

I thought an apples to apples QL comparison of cartridges using the TTSX would be interesting (mainly because I prefer not splashing lead into my meat). Even if they don't compare well to ABLR or MTH because of the higher expansion velocities. I didn't want you to have to QL every single one, but it would be an interesting way to compare them using similar hunting bullets if you did. So I thought the most interesting ones of the group were the .257 80gr and the .264 100 grain as per Litz form factor numbers. Since they have the most efficient shapes among the TTSX, in theory should retain impact velocity the farthest. And I did mean QL numbers, not real world data.

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ok here are all the bullets with a 24 inch barrel you can take the numbers and run them.

Posted: 3/4/2019 9:33:56 PM EDT

[#45]

From AB: (2k@ means 2k fps impact velocity at given range)

Speed: BC: Cal Gr Imp.Vel@yds drop"/drift"@400yds
3203fps .159G7 .243 80 TTSX 2k@415yds -24"/16.92"
3286fps .146G7 .257 80 TTSX 2k@405yds -23.3"/18.1"
2923fps .181G7 .257 100 TTSX 2k@375yds -28.7"/16.5"
2916fps .175G7 .264 100 TTSX 2k@360yds -29.2"/17.2"
2819fps .172G7 .277 110 TTSX 2k@320yds -32"/18.5"

As with all things .277, the 110TTSX is a disappointment.

The .257 80TTSX is the flattest shooting, and still hits like a point blank 10mm at 415yds. The extra diameter would help it a bit in shorter barrels over the 243. The .257 100TTSX is the most accurate in wind.

Assuming 30fps per inch loss, 18" would make 3100fps with .257 80gr. 2k impact velocity at 350yds. MPBR zero at 300yds out to 375yds with 8 inch vitals. I'm liking the modern quarterbore..

Posted: 3/4/2019 9:38:24 PM EDT

[#46]

Here is some 18” 25x6.8 data. Temps at 4 degrees so it will be faster in normal temps. A lot of the data was experimental but you can see when loads were figured out.

Not my data.

https://drive.google.com/file/d/0B1Qr2nzNOTotZE5NUGU4ODdfV00/view

I have a 25x68 barrel and dies, but haven’t gotten around to building it yet.

Posted: 3/6/2019 2:13:57 AM EDT

[#47]

finished building my 20 gpc and making some brass

24 inch rifle gas barrel, bear creek side charge upper that i milled out to fit the six8 pattern lowers and mags -- the 20 don't need the length but i want to get the sulzer set up tested. topped it off with a vortex diamond back 6-24 ffp scope.