300 Norma Improved 35 degree

[GlennK]

Glenn, which pilot are using?

Pilot 67

 

[Alex Wheeler]

I have been trying different barrels to see how the different bore volumes and rifling designs work out. I am currently working with a 26" Brux #5 on a Bat HR. I have a Rock Creek 5r and a Lilja 3 groove to work on as well.

This Brux was on the big size as far a groove diameter, so work up to this load it will be hot in other makes and lesser actions.

I have worked with H1000 and N570, as well as federal 215s and cci 250s and the 230 Berger. So far 92.3 of N570 has held less than 1.5" of vertical at 600yds the last 4 times I have shot that load. .005 off the lands has given the widest tune. The cci 250 has grouped better as well. Velocity between the two primers was very close.

Velocity is 3090 fps in a 26" 9tw Brux with a 230 Berger .005 off the lands, cci 250, .002 nt, 92.3 of N570. No pressure signs at all, roughly 150 rounds on the barrel. Please work up to this load. Bat HR actions have lugs sized intentionally for these cases and can take a lot of pressure.

Every Krieger so far has prefered H1000, this Brux did not love H1000, N570 was the clear winner.

 

[Alex Wheeler]

Also, this is the 3rd barrel I have tested annealed vs non annealed and so far non annealed has shot smaller every time for me.

 

[MTlager]

Are you using a smaller bushing after you anneal for more neck tension, or staying the same ???

 

[Alex Wheeler]

I have went as much as .009 with annealing. Mostly .001-.005. Even tried the mandrel with annealing. Lubes did not prove better either.

 

[Alex Wheeler]

Are you using a smaller bushing after you anneal for more neck tension, or staying the same ???

I have a Bench source. Glenn has been shooting some of the smallest groups I have seen for a big 30 with his 300 NMI. Hes running 4-5 nt with annealed brass but he has an amp.

 

[mdbruce]

I have a Bench source. Glenn has been shooting some of the smallest groups I have seen for a big 30 with his 300 NMI. Hes running 4-5 nt with annealed brass but he has an amp.

Is the testing annealed vs. non-annealed because the on-target benefits to annealing are still questionable?

 

[Alex Wheeler]

Annealing is just like any other tuning process. Its not a given. Sometimes it improves groups other times if make them open up. You have to test it and see how the load responds. Annealing softens the brass and effects the amount of grip the brass will have on the bullet for a given "tension".

 

[mdbruce]

Cool - Thank you, Alex

 

[Kratos]

I assume the freebore would need to be increased for the A-tips?

 

[Alex Wheeler]

I have 3 reamers depending on the bullets a guy wants to shoot. The 250 a tip are so long you almost marry yourself to them.

 

[Alex Wheeler]

I have arrived at the final tune for this barrel after doing powder, neck tension, primers, one last seating depth test this morning. .020 off and .005 off have been shooting great at 600 and I finally got good enough conditions to shoot 1000. .005 off was the clear winner shooting a round 3.8" group. 230 Bergers, -.005", .0015" neck tension, non annealed brass, cci 250, 92.3 gn of N570 for 3100 fps in a 26" barrel. 19.8 moa to 1k. This is on the mid length throat.

 

[B23]

I have arrived at the final tune for this barrel after doing powder, neck tension, primers, one last seating depth test this morning. .020 off and .005 off have been shooting great at 600 and I finally got good enough conditions to shoot 1000. .005 off was the clear winner shooting a round 3.8" group. 230 Bergers, -.005", .0015" neck tension, non annealed brass, cci 250, 92.3 gn of N570 for 3100 fps in a 26" barrel. 19.8 moa to 1k. This is on the mid length throat.

Not much to complain about with that load/setup! I'd bet most would be thrilled with a final load that shot that well.

 

[Alex Wheeler]

I have been happy with it. I dont look at the small groups so much as I look for day in day out consistency. This load has shot as small as an inch at 600 up to 2 1/4". Thats over about 7 or 8 range trips on different days with different conditions. I have had tunes that would shoot tiny tiny groups but were touchy. I also watch for horizontal on these. The larger magnum cases with slow powders seem to have a tenancy to shoot wide groups with very little vertical. You can get fooled into thinking its a good tune and you just got caught in conditions. So I am looking for round groups more than the tightest vertical.

 

[kev77]

I have been happy with it. I dont look at the small groups so much as I look for day in day out consistency. This load has shot as small as an inch at 600 up to 2 1/4". Thats over about 7 or 8 range trips on different days with different conditions. I have had tunes that would shoot tiny tiny groups but were touchy. I also watch for horizontal on these. The larger magnum cases with slow powders seem to have a tenancy to shoot wide groups with very little vertical. You can get fooled into thinking its a good tune and you just got caught in conditions. So I am looking for round groups more than the tightest vertical.

Out of curiosity is there a reamer and matching set of dies I can buy. Looking for one stop shopping if possible. For us Canadain dudes. Thanks very much

 

[Alex Wheeler]

Not really. I do not sell reamers or dies except with rifles I build. I get my reamers from JGS, dies are from Hornady or I make them. Improving a case like this is very basic stuff. There is not much to it.

 

[Tucker65]

Out of curiosity is there a reamer and matching set of dies I can buy. Looking for one stop shopping if possible. For us Canadain dudes. Thanks very much

I purchased my reamer from Manson and then sent the reamer print to Whidden Gun Works and they made a nice custom set of dies that work great.

 

[Alex Wheeler]

The only real advice I can give you is to talk to who ever is making your die and make sure they understand how this brass acts. If they want to make a die with similar specs that they would use for "normal" cases I can promise you that you will get clickers once you get into the higher pressure loads. This brass is tough! And you need the dies designed right to prevent clickers.

 

[rhovee]

You can’t use the same process as you would for smaller cases. I can promise you that. And Whidden made me a custom 338 edge die that doesn’t work properly because I didn’t specify any measurements. Just had them built it how they normally would.

 

[Dm6]

Where could you get a seating die for this if you don’t want to use an arbor press? Does anyone sell dies or would you have to wait for a custom one?