300 Norma Improved 35 degree

[Tekardi]

Run some loads and this one convince me for next 1 mile + shoots, clickers are gone with full sizing as advice , very low pressure in this load R50 , 93 grn , 250 A Tips, OAL 3.8075 ( 2940-2962 fps ) 5 shoots
Bushing 336
No anneal
Stab factor 1.74
Will see how it goes sending 20 or more A Tips consecuently , always thinking not to shread them ( 265500 revs a minute ) but I have no 230 or 245 s burgers down here ....

 

[Usas]

Question to those that are using proof barrels.
i have a 26in sendero profile
PTG NMI reamer spec 341NK lapua brass. Neck trimmed for cleanup
Currently my load is 87.6gr of Retumbo, 245gr bergers @ 2.773 base to ogive.
Velocity 2945fps with sd of 5 or 6 over 30 rounds. 130 rounds down the barrel.
I'm getting a reasonable and consistent 3 round departure from the group. First 2 are generally within .2moa or better and 3rd will open as far as 1 moa.
Firing protocol is 3 rounds with no break in between, then allowing barrel to completely cool between groups.
I'm thinking the proof can't stand the heat... how are you guys shooting proofs finding the thermal shift with the NMI
I have a bedded defiance action FYI.

 

[Alex Wheeler]

If I am asked, I recommend Bartlien for carbon. They leave a little mote steel on the blank and rifle after wrapping. Have had a lot of problem with some other brands

 

[Usas]

If I am asked, I recommend Bartlien for carbon. They leave a little mote steel on the blank and rifle after wrapping. Have had a lot of problem with some other brands

Yeah that certainly would have been my preference, though availability was an issue when I built this one. I tested again today, this time I waited 4mins between shots, which brought the 3rd round back into line. This barrel does seem fickle, with tight nodes, coupled with my ability to shoot a 12lb freight train with a 3 port brake.

 

[Tekardi]

Done again ...300 NI AW 35 ! For the win in Grand Slam Argentina !

 

[Darkside]

Done again ...300 NI AW 35 ! Grand Slam Argentina !

Well by God if you have a Tank for backup, you should have done very well.

 

[MagnumW]

Done again ...300 NI AW 35 ! For the win in Grand Slam Argentina !

Congrats!!!! Very Impressive ! Been years since I went thru the straits - gotta get down there again.

 

[Ledd Slinger]

Question to those that are using proof barrels.
i have a 26in sendero profile
PTG NMI reamer spec 341NK lapua brass. Neck trimmed for cleanup
Currently my load is 87.6gr of Retumbo, 245gr bergers @ 2.773 base to ogive.
Velocity 2945fps with sd of 5 or 6 over 30 rounds. 130 rounds down the barrel.
I'm getting a reasonable and consistent 3 round departure from the group. First 2 are generally within .2moa or better and 3rd will open as far as 1 moa.
Firing protocol is 3 rounds with no break in between, then allowing barrel to completely cool between groups.
I'm thinking the proof can't stand the heat... how are you guys shooting proofs finding the thermal shift with the NMI
I have a bedded defiance action FYI.

I had a Proof on my last 300 NMI and didn't have heat flier issues. Sometimes would shoot two or three 3 shot groups without much cooling time between groups and still no issues with fliers. (220gr Berger and 92gr N570)

At 130 rounds, your barrel is probably finally breaking in so the load will have to be tweaked for charge weight, seating depth, or both.

However, I have experienced a flier in groups more times than I can count when testing Retumbo in many different chamberings, including the 300 NMI with Proof barrel. I wont even waste time testing with Retumbo anymore. I would start by ditching the Retumbo and try VV N570, VV N568, RL33, or RL50 with the 245gr Berger and I'm sure you'll find a good consistent load.

On another note, I was never able to get the 245gr Berger to shoot nearly as good or consistently as other Bergers. The 215gr, 220gr, and 230gr always shot better than the 245gr for me. Tested all those bullets in 8" twist and 9" twist barrels. Now have a 10" twist barrel on my 3rd 300 NMI build but won't be running any 245s thru it

 

[Ledd Slinger]

Has anyone tried N565 in the NMI? I almost bought some the other day, but thinking the burn rate might be a little fast for 215-230gr bullet weight range. N570 is what I currently use which of course is pretty slow burning but gives good speeds and temp stability. N565 is a couple steps faster than H1000 so not sure of it will work with the 220gr Berger. I do have N568 on hand as well for testing but was wondering if anyone has results from N565? Thanks

 

[Wildcats]

Get your hands on some N568 ,i hear that it works well in the 300NM

 

[taylorw]

Has anyone tried N565 in the NMI? I almost bought some the other day, but thinking the burn rate might be a little fast for 215-230gr bullet weight range. N570 is what I currently use which of course is pretty slow burning but gives good speeds and temp stability. N565 is a couple steps faster than H1000 so not sure of it will work with the 220gr Berger. I do have N568 on hand as well for testing but was wondering if anyone has results from N565? Thanks

View attachment 1464289

Posts #212&217. These are true & accurate numbers so use them with confidence.

 

[otnot]

I ran up Stabal HD from 84 gr. at 2859 fps to 89 gr. at 3081 fps. At 89 I still wasn't showing any pressure signs and I need to try 90+ grains. The best group was at 88 at 2960 fps.

I also tried US 869 and started at 99 gr. at 2995 and went to 102 gr. at 3129.

All these loads were with a Hornaday 230 gr. Atip and Fed 215 primers and Peterson brass and at 60 degrees. And my gun is 300 NMI.

 

[Ledd Slinger]

Posts #212&217. These are true & accurate numbers so use them with confidence.

Thanks! Figured it was in here somewhere. Lol

Seems very close to H1K characteristics.
I'm starting with N568, N570, and H1K. Will keep N565 in mind.

Few pics of my 3rd NMI build.

 

[Ledd Slinger]

Those are the 2 best options. Since bat went to a 2 piece bolt the decision is difficult. About the only thing bat has on the borden is an integral rail. But the borden is pinned so it not going anywhere. You cant make a bad choice here

Exactly how does the BAT two piece bolt design inhibit accuracy, function, or strength when it breaks down all the way on the rear of the bolt body at a spot that it fully encapsulated by the receiver raceway?

Maybe I'm wrong, but speaking from a mechanical point of view, I can see no issues with the design. It breaks down at a point that has virtually no stress or recoil forces and the raceway will keep the joint aligned just as good as a one piece. no pins or other drag points on the firing pin either. It's a far better design than any action like Savage or Origin with swappable bolt heads.

 

[Alex Wheeler]

Exactly how does the BAT two piece bolt design inhibit accuracy, function, or strength when it breaks down all the way on the rear of the bolt body at a spot that it fully encapsulated by the receiver raceway?

Maybe I'm wrong, but speaking from a mechanical point of view, I can see no issues with the design. It breaks down at a point that has virtually no stress or recoil forces and the raceway will keep the joint aligned just as good as a one piece. no pins or other drag points on the firing pin either. It's a far better design than any action like Savage or Origin with swappable bolt heads.

Its a joint, no matter how tight theres some movement. In the cocked position there is more shroud lift with this design because the joint is in the rear. Shroud lift means more potential for increased vibration and firing pin drag. Bat did make a solid sleeve because I was not happy with the movement and that reduced it a lot. So the solid sleeve is an option for guys. I have not noticed any accuracy decline, but these are not bench guns either. Given a choice I prefer the one piece bolt. The joint has not stopped me from using them, I just really wish they would have stayed with a one piece bolt. For the money, I think we should get a solid bolt. Just my opinion.

 

[WSnyder]

So the solid sleeve is an option for guys.

That's good to know. I made a solid sleeve for one of mine so far and that will be a nice timesaver. I will reach out to see if I can purchase a couple of them.

Oh and the split sleeve does have give to it. You can tap the two bolt halves back and forth into miss-alignment with them so there is play. I did not like that part at all.

 

[Ledd Slinger]

Its a joint, no matter how tight theres some movement. In the cocked position there is more shroud lift with this design because the joint is in the rear. Shroud lift means more potential for increased vibration and firing pin drag. Bat did make a solid sleeve because I was not happy with the movement and that reduced it a lot. So the solid sleeve is an option for guys. I have not noticed any accuracy decline, but these are not bench guns either. Given a choice I prefer the one piece bolt. The joint has not stopped me from using them, I just really wish they would have stayed with a one piece bolt. For the money, I think we should get a solid bolt. Just my opinion.

That's sound reasoning on the shroud lift. Definitely possible.

I have been testing the bolt body for deflection after reading that post a while ago.
I found the highest point for zero at my measurement location on the bolt body. Then applied significant downforce on the joint with my hands, far more than the joint would ever see under normal operating conditions, and checked it again in the same exact spot. Did the same by taking the bolt and bending at the joint upward, like trying to snap a twig, then checked again in the same exact spot. Flipped the bolt and did the same test at multiple points. Tried pushing and pulling, then hitting the bolt at the joint on a table, and rechecked. In ALL tests it remained straight and true according to my measurements.

I can see a potential for issues if there were slight machining errors for fit at the joint between different bolt bodies or if it took an extremely hard hit, but the bolt on my HR is very solid. Nothing to worry about as far as I can tell.

 

[Ledd Slinger]

The data for N568 seems to be pretty lacking in the NMI. Thats where I'm gonna start with this new rifle so we have a little more info in this thread's database.

Loaded up 2 different 10 round pressure strings for testing. One set with GM215M primers and the other set with CCI 250.

Loads have 220gr Berger at -.010" jam and .004" neck tension. Strings start at 90.5gr and graduate up to 92.9gr.

27" Hart barrel with 1 in 10" twist that will have exactly 50 rounds on the bore when I start the first 10 shot ladder

As far as case fill goes, i had no issues at all getting enough N568 in the case using my short funnel that's built into the side of the pan (shown in pic) and dumping at normal speed. I tap the case on one of my granite blocks multiple times after dropping the charge and even 92.5gr settles around the Shoulder/Body junction. With my seating depth on the 220gr, I'm not even compressing the load. Just to see, I loaded as much N568 as a I could until the powder came up to the bottom of the case neck with the same short funnel. Tapped on granite to settle the charge and it weighed in at 97.7gr. So I think there's definitely enough room in the case to find pressure with 568.

My reamer design is very similar to Alex Wheelers design. So close that I'm actually using the Wheeler custom Hornady FL bushing die. Therfor, this data should also be applicable to anyone running a barrel with Alex's reamer. I know I can shoot 600 yards, but I think I found a spot where I might be able to shoot 860+ yards if Google earth isn't lying to me. Will report back with data when strings have been fired.

 

[Alex Wheeler]

That's sound reasoning on the shroud lift. Definitely possible.

I have been testing the bolt body for deflection after reading that post a while ago.
I found the highest point for zero at my measurement location on the bolt body. Then applied significant downforce on the joint with my hands, far more than the joint would ever see under normal operating conditions, and checked it again in the same exact spot. Did the same by taking the bolt and bending at the joint upward, like trying to snap a twig, then checked again in the same exact spot. Flipped the bolt and did the same test at multiple points. Tried pushing and pulling, then hitting the bolt at the joint on a table, and rechecked. In ALL tests it remained straight and true according to my measurements.

I can see a potential for issues if there were slight machining errors for fit at the joint between different bolt bodies or if it took an extremely hard hit, but the bolt on my HR is very solid. Nothing to worry about as far as I can tell.

View attachment 1466434

I did all my testing with the bolt in the action. In the cocked position there was significantly more shroud lift vs a solid bolt. I also stripped everything down and pried up on the shroud while it was in the action to the same amount so I could test for drag on the striker. Surprisingly in that case there was none, however I am confident that was the exception. I retested this when Bat made the solid sleeve and that brought the shroud lift down considerably. Not quite as good as a solid bolt, but close. So, in my opinion theres nothing to worry about if your using a solid sleeve. But I still miss the solid bolts. The HR was absolutely the perfect 700 clone to me, I couldnt find anything to bitch about.

 

[Ledd Slinger]

I did all my testing with the bolt in the action. In the cocked position there was significantly more shroud lift vs a solid bolt. I also stripped everything down and pried up on the shroud while it was in the action to the same amount so I could test for drag on the striker. Surprisingly in that case there was none, however I am confident that was the exception. I retested this when Bat made the solid sleeve and that brought the shroud lift down considerably. Not quite as good as a solid bolt, but close. So, in my opinion theres nothing to worry about if your using a solid sleeve. But I still miss the solid bolts. The HR was absolutely the perfect 700 clone to me, I couldnt find anything to bitch about.

Yeah I have no need for swapping bolt heads. I tried a switch barrel one time with interchangeable heads and pre-fit barrels and will never do it again. Be nice to have a solid bolt on the HR for reasons stated, but it's still arguably the best 700 clone out there in my opinion. Everything just lines up and times out so perfectly. No question on strength either because, to the best of my knowledge, BAT is still the only action manufacturer that uses the 17-4 stainless steel instead of the 416 used by everyone else.