20-250 data

[Gabe22BR]

Doug, I tested my 20BRAI, the other day, using 32.5grs of RL15, pushing the 55gr to 3853 fps. Accuracy was great @ 300yds, and no pressure signs. My accuracy trumps speed here, so I stopped any further load development. I will be tweaking it though, w/ primer change/ test next..
I used the 250 load data from this site to get to a starting point for my BRAI. Since there isn’t a lot of 20 BRAI data out there, & case capacity is about the same.

 

[Doug30racer]

Which primer? reg or magnum

 

[Gabe22BR]

I used the cci 450
Plan to try the BR4 & Fed 205M

 

[Scooby-93]

Doug, I tested my 20BRAI, the other day, using 32.5grs of RL15, pushing the 55gr to 3853 fps. Accuracy was great @ 300yds, and no pressure signs. My accuracy trumps speed here, so I stopped any further load development. I will be tweaking it though, w/ primer change/ test next..
I used the 250 load data from this site to get to a starting point for my BRAI. Since there isn’t a lot of 20 BRAI data out there, & case capacity is about the same.

that is some velocity for such a low charge weight!

what is the length and twist of barrel?

 

[Gabe22BR]

Pacnors best 3G 9 groove 27”

 

[Gabe22BR]

The BR case is more efficient

 

[Scooby-93]

Pacnors best 3G 9 groove 27”

great feed back, which action? are you running it single feed or as a repeater?

 

[Gabe22BR]

Borden BRM drop port

 

[xswanted]

The BR case is more efficient

I would say it handles pressure better in this particular instance.

Efficient yes, but the BR cases will stand up to high pressure loads better than a 250 case will. Even with Lapua brass

I’ve had both a 20BR (standard) and a 20-250 and when push comes to shove, the 250 will produce more speed simply because you can ram more powder in there.

The BR is impressive but there is no substitute for case capacity.

My guess is the 20BRA will have better barrel life by 250-500 rounds depending on the user though.

 

[Scooby-93]

I’m hoping to achieve 4300 FPS with 39sbk in a 10 twist 26” with viht n550

 

[B23]

I would say it handles pressure better in this particular instance.

More accurately, the BR case hides pressure better. A case like the BR case with so little taper hides pressure signs better than a case with more taper.

 

[xswanted]

More accurately, the BR case hides pressure better. A case like the BR case with so little taper hides pressure signs better than a case with more taper.

Yep, that is the word I should have used.

I think a lot of people, myself included, would be shocked at what kind of pressure they are running in any of the 6BR wildcats and variants.

 

[Gabe22BR]

More accurately, the BR case Handles pressure better. .

Fixed for ya

 

[B23]

Yep, that is the word I should have used.

I think a lot of people, myself included, would be shocked at what kind of pressure they are running in any of the 6BR wildcats and variants.

You Sir would be in the great minority because very few are ever honest about it or don't want to admit that. Instead, you hear folks talk about these crazy fast velocities and then claim, "and that's with no pressure". Guess they don't realize you get those crazy fast velocities because of pressure.

 

[xswanted]

You Sir would be in the great minority because very few are ever honest about it or don't want to admit that. Instead, you hear folks talk about these crazy fast velocities and then claim, "and that's with no pressure". Guess they don't realize you get those crazy fast velocities because of pressure.

Yep.

I’ve reloaded long enough in my 38 years that speed is a byproduct of pressure when it comes to rifles. There’s no magic.

If you want more of it, get a bigger case.

Having said that, I like to push the limits as well but I feel I’ve learned enough over the years to know when to stop.

Agreed that too many people use the “normal signs” of pressure and if they don’t see those, it’s safe.

I wish it was possible to have my own PSI gauge to test pressures in my own rifles. I think I’d probably be surprised I’m a lot of loads they are higher than even I think they are.

Some guys would be near proof.

The BR case is one of those cases that is, in my opinion, easily loaded well past the pressure it should be loaded but due to good brass and we’ll made actions very few people blow themselves up with it.

The Creedmoor case is the new one that is getting out of control. To many people basing loads off online stuff they read.

Still need to be safe!

 

[Scooby-93]

Anyone had any fluctuations in pressure with there 20’s? Loaded up to 38.5gr of n550 with no pressure but at 38.5 the primer was flattening then 39gr the bolt was heavy. 39gr resulted in 4350fps with 39sbk.

I then done a OCW test from 37.2-38gr

I hit pressure at 37.4gr?

I done another OCW 36.2-37gr.

Accuracy node was 36.6 so went with that.

2 out of 6 rounds at 36.6 have had pressure signs in the form of a sticky bolt.

I can’t put my finger on why initially 38.5gr was the start of pressure and then all of a sudden I am getting intimating pressure at 36.6?

same batch brass, primers, bullets and powder. Temp has been the same give or take a few degrees.

there is no a total of 75 rounds down the tube with the break in procedure of x10 1 shot clean x3 3 shot clean x2 5 shot clean.

butchers bore shine is what I have used to clean, I have pulled a lot of carbon out the barrel but it’s took a lot of patches and brushing.

barrel is a bartlin 10twist

 

[OKyote73]

Was the initial rounds on unfired brass? Could be the issue

 

[Scooby-93]

Was the initial rounds on unfired brass? Could be the issue

Yes all rounds fired on virgin brass,
Brass was prepped as follows

Lapua Brass necked down in 3 steps with Forster bump bushing die to .230 bush, then expanded in K&m expander and neck turned to .230, I then put them
Back through my bushing die before uni forming the primer pockets and chamfering the case necks.

camber neck is .234

 

[L.Sherm]

I used the cci 450
Plan to try the BR4 & Fed 205M

Mine likes the 450 and RL15 with 55's and 46.5. Bullets

 

[Gabe22BR]

I pierced a cci 400, & the 205M was normal, as was the CCI 450