FatBoy's 6 Dasher Norma

[FatBoy]

finally got around to ordering a barrel for the Dasher build.

Specs:

Barnard P
Krieger 30" Light Palma, 1:7.5 twist, .237"
PTG Norma Chamber from Bullets.com
B1 tubegun chassis
Nightforce NXS 3.5-15x50

Limiting the primer, bullet and jump. Just looking for pressure, basic MV and basic accuracy. Barrel has zero rounds down the pipe so I understand MV will increase some after 100-150 rounds. It's also cool here, so I will re-work the loads when the barrel is seasoned and we have some heat outside. I prefer to test in the 90* F range but I'm not waiting 5 months.

Throat is shorter than I expected, at 1.825" base to ogive with a 107SMK, but the bearing surface starts above the neck shoulder line so it should be fine. Cases were lubed and ran under a K&M mandrel to square the necks and then chamfered.

Current test loads for this weekend: EDIT to add some lighter loads

5 x 31.2gr Varget, 450M, 107SMK .018" off
5 x. 31.6gr Varget, 450M, 107SMK .018" off
10 x 32gr Varget, 450M, 107SMK .018" off lands
5 x 32.5gr Varget, 450M, 107SMK, .018" off lands

5 x 33.3gr 2000MR, 450M, 107SMK .018" off
5 x. 33.6gr 2000Mr, 450M, 107SMK .018" off
10x 34gr 2000MR, 450M, 107SMK, .018" off lands
5 x 34.5gr 2000MR, 450M, 107SMK, .018" off lands

I get that I may lose pockets. If that's the case, so be it. At least I'll know. I'm not forming brass for a highpower prone rifle. This stuff needs to go 7-10 firings (2000 rounds) and then it's going in the trash with the barrel.


Hope to be out Saturday running them over a 35P Chrono. If all goes well, I'll pick a load or two, load 23 of each and take it to 600 Sunday, three shots on steel to zero and then run 20 into a paper target.

I'll update as I have info.

 

[FatBoy]

Yup, no mistype. If I am reading the threads correctly most guys are getting up to 33gr Varget so I figure starting a grain low will be fine. I may regret that but it's not gonna hurt a Barnard.

Yes, brand new brass.

 

[22DASHER]

The last thing I would do is start at 32 or 32.5 grains with new Norma brass. I usually start at 32 grains with formed Lapua and Norma is not even close to that. This brass needs to be loaded atleast a grain less on its first firing... but anyways you do what you want. It's not my brass, boltface, barrel or eyeballs.

 

[FatBoy]

I am clearly missing something. This isn't my first rodeo loading, but for some reason the Dasher is looked upon unlike any other chambering. I'm not tying to be obtuse, but I don't see how this is any different than starting with 29gr of varget in a 6BR? How may people work up to 29? My bet, nobody. They go right to 29 and work up the half grain-grain.

What am I missing here? Putting 5 more rounds together with 31.6~ish isn't a big deal. If this sh-tuff needs to be fired twice before it can be shot in a match it's worthless.

 

[22DASHER]

The difference is new Norma dasher brass is not the same as formed Lapua brass. Even once fired Norma isn't the same. I already made my own mistakes thinking Norma brass was the same as Lapua... it's not.

 

[FatBoy]

Good luck with that.

Curious what you think the issue is, George. I recall your load is close.

 

[FatBoy]

I'm wondering if my expectations of this brass is different than you guys? I don't need it to last 20-30 firing. 32gr may be higher than the pocket will handle. If so, I'm out 2-10 pieces. I don't expect it will pierce, but I may just be optimistic.

I'll load up some a half grain lower to start, but again, if I can't go strait to at least 2950 this is a worthless chambering for me. Fire forming is pointless in a highpower rifle.

 

[lloydx2]

That's a .104 fb reamer. I am thinking with the longer chamber (neck)
you should be ok. I ran 32.5 varget 105 hy 10 in @ 2970-90. This was
first firing in Krieger .236. no turn .272 nk. 1-8 twst I have the old lapua
chamber reamer .125 fb .1555 chamber oal. I am trimming the norma.
How far out of the neck shoulder is the base of the bullet chris.
I was thinking of ordering a norma reamer. Maybe longer fb? Let us know.
I think the norma brass is great, It has its place. If your looking to run just
below max pressure. Go get it.

 

[FatBoy]

The throat actually concerts me a little. My 6BR is .045" longer with the same bullet. I can have it throated if needed but Tim's not gonna be happy.

pic is .018" off the lands with an unfired case as the case gauge to measure.

 

[FatBoy]

I'm loading up three each 31.3/31.5 varget loads and some 33.3/33.5 2000mr loads. No point of etching a firing pin being lazy.

 

[swd]

I put together a Norma Dasher on a 700 a couple months ago. 7" twist X Caliber, bullets.com PTG reamer. I throated it out another .040". I threw together a load just to shoot for fun. 31.5 Varget 450's and a 107 SMK .010" off. No load development. The primers while not showing max, definitely show it's not a long ways off. It will probably make it to 32.5 but it will probably be MAX in my rifle.
Life has gotten in the way of running it across the chrono but with no load development at all it was grouping around 2.5" at 500 off a Harris just shooting steel to impress the land owner of a new ranch I recently got access to shoot on.

 

[FatBoy]

Is your pin bushed?

 

[swd]

Is your pin bushed?

No but it's the outside of the primers starting to square up pretty good. Yes I am getting some cratering but it's not too bad yet. More powder and I'll probably have to bush it.

 

[FatBoy]

Just checked up and added:

5 x 31.2 Varget
5 x 31.6 Varget

5 x 33.3 2000MR
5 x 33.6 2000MR

 

[lloydx2]

Its hard to tell from the pic It look like the bullet is out quite a ways
Norma 1.605 chamber length with 104fb. Compared to Lapua. 1.555 with .125fb
my chamber has .029 less max overall length. (bolt face to bullet shoulder contact with lands)
The Norma should have more chamber volume I would think if the Norma chamber
had more free bore you could really tip the horn in it.
The Lapua chamber I am referring to is a Dan Dowling print from PTG with a 272 nk
.125 fb 1-30 ld. For the most part from the neck-shoulder back to the case head Daves
Dasher prints are the same. With some exceptions to case head diameter

PS probably better to back off a little. You don't want any craters on that new Barnard
blot face, Let us know Lloyd

 

[swd]

31.2 of Varget should be fine to start with.

 

[Eric Leonard]

I was thinking about having a Norma Dasher done also but if I am gonna have to fireform the Norma Brass I will probably do an XC or a 6x47L,,

 

[FatBoy]

Robert Whitley has a load test post on here with two different barrels. One showed some issues with N140 but others with Varget and 2000MR showing good luck with virgin brass and decent speed. He had a couple different barrels, main one being a Bartlein. It's worth searching for.

If my tests mirror his I think it's probably a pretty safe bet. If not, there's always 243Win.

 

[tclaunch]

I was thinking about having a Norma Dasher done also but if I am gonna have to fireform the Norma Brass I will probably do an XC or a 6x47L,,

The rim thickness is the only issue with Norma brass, and has been corrected. Next batch should be incredible. I'd like to know how much longer that will be. I'm thinning the rims on 200 pieces for someone now. The new stuff won't need that. The Dasher has earned a spot well ahead of the XC or 6x47.
All brass needs a fireform load to shoot best.

 

[idahoorion]

I put one of these together and love it. however, I was a little later than some on this forum so I got the benefits of the earlier discussion. Norma dasher brass, bullets.com reamer, K&P barrel @ 26" finished. 105's amax, hpbt, berger hybrids, CCi 450's. and like reported by others, with Rl 15 and varget I was getting stiff bolt lift and some shiny ejectors marks before getting the FPS I was looking for. (close to or 3000 fps). great accuracy tho. So I got some MR 2000 and worked it up and am at 2978 with room to go higher but my gun loves this speed and we are staying put.
I shoot it in virgin brass or fired and it's no issue. Accuracy is the same, and bolt lift and brass, primers etc look great.
I am a bit higher with the my load than what your higher testing load is Fatboy.

I had no previous experience with 6br or any of the variants, and thanks to info presented on this forum was guided into a load combo that was easy to work up and satifies my needs. For me, no fireforming and loading and shooting is the easiest or one of the easiest of any cartridge I've ever loaded for.

Idahoorion