300 Norma Improved. Load testing, info, and builds

[wolffman]

Thank you sir for the detailed quick repsonse! I will do what you said and go from there. I always clean the tips out and have never had a problem yet. Looking forward to trying the 245 out.

I am running HS precision detachable mag. Would your fix work with this ?

 

[rpierce]

No problem. Not sure if it will or not. I haven't had one of those magazines in the shop. Im using the Accurate magazines with a 3.770 internal length.

 

[rpierce]

Well I decided to throw my 338 norma improved barrel on my borden setup. I grabbed 6 pieces of hydro formed brass and got it dialed in at 100 with 86 gr of h1000 and 300 gr bergers. 4 of the 6 shots had a ES of single digits at 2705 fps. The 2 fliers were 20 fps slower. I figured I was at the bottom of the node.

I loaded up 3 rounds of 86.3 gr and backed it up to 580 yds. 1.450"/.238 moa at 580 yds for the 3 shots. ES of 10 fps. Easiest load development for breaking in a barrel Ive seen so far LOL. I took a video of Brock shooting it while breaking it in. I had thrown my titanium cheytac brake on it. Kills the recoil. I can watch vapor trail and spot hits no problem with this forming load. Recoil about like the 300 norma improved. Not bad at all. Wouldn't have a problem letting my wife shoot it.

After she gets broke in and speeds up Ill try some n570. In my 32" barrel I didn't hit pressure until 3100 fps. Guessing Ill hit pressure around 2950-2975 in the 26" barrel. If I get a accuracy node at 2900 Ill be happy.

 

[Epirate43]

I think one of these 338 Norma AI are in my future. Ryan are you liking the Borden Bigfoot over the Kelblys?

 

[rpierce]

I think one of these 338 Norma AI are in my future. Ryan are you liking the Borden Bigfoot over the Kelblys?

Yes. Every single borden is dead straight, comes with a timed ignition from borden, and has an integral recoil lug. Not sure if the bigger threads is a big benefit but in theory it is. Itll help eliminate bolt click. However by the time Ive gotten bolt clicks on kelbly or bigger actions the case head has expanded. The bigger lugs on the borden should help with lug setback. I measured it on a Kelbly with 1500 rounds and it wasn't much. However I measured it on a different action with very small lugs and it had .0015 in 200 rounds. Now that was on a 33xc with warmer loads. However that amount in 200 rounds is excessive.

 

[Epirate43]

Thank you for the info. I will be in touch

 

[rpierce]

Thank you for the info. I will be in touch

no problem. sounds good.

 

[rpierce]

Well I did a ladder test with my 338 Norma Improved, 300 gr Elite Hunters, and N570. I found a sweet spot between 92-93 gr. It had a very faint ejector mark. At 93.5 gr the case web expanded .00025 more than the 92 gr load. 93.5 gr was 2907 fps. I had to use a 12" drop tube and pour slowly to get this much powder in. Wasnt a fully compressed load with the drop tube.

I loaded up 3 rounds of 92.1 gr. I shot 3 shots at 580 yds. The last shot went to the right. I figured it was caused by the wind dropping off since the brush stopped moving. So I went back inside the shop and loaded 2 more rounds up. Brush had started moving slightly again right to left so I aimed dead center. They went into the same spot as the first two shots.

1.185"/.195 moa vertical for 5 shots at 580 yds.
300 gr Berger at 2865 fps.

Ill do a quick seating depth test next time its nice out and call load development done for N570.
Cant wait to try some N568 when my big shipment comes in. I think itll be a little more optimal and the 12" drop tube won't be necessary. The N570 kernals are huge and take up a bunch of space. 1 kernal is .08 gr on average. N568 is smaller kernals.

 

[E4aker]

Ryan, how is extraction with the .338 Norma imp. I see the body taper on the SAAMI spec reamer is only .06299 tpi, seems like it would be inadequate.

I normally see improved cases with .100-.120tpi

 

[rpierce]

Decided to do a powder charge test yesterday at 580 yds with the 300 Norma Improved with 230 OTM bergers and VV N568.

Gave the scope 3/4 moa of left wind after the two fouler/zero shots. 10 shot 5 gr spread powder with .5 gr increments was 2.56"/.42 moa vertical at 580. Wind was 10-15 mph.

Loaded up 4 rounds of 90 gr. Wind was a solid 15mph at this point.
ES OF 7fps.
2.4"/.395 moa vertical with a flier.
3 out of 4 had .6"/.098 moa of vertical.
Being 5 gr under slight pressure will give very minimal throat erosion and the brass will last indefinitely.

Ive tested the 230 otm in 3 different rifles now and its been the most forgiving and easiest 30 cal bullet to tune so far. Ill do a couple different seatings depths at 1000 in the next week or two.

 

[Shane Lindsey]

So Ryan at 580 yards how would you pick this out? It all looks like the winner to me. I would pick either my higher for hunting or low for a little more brass life.

Nahh high velocity all the way.

 

[highdrum]

@rpierce is this a seasoned barrel or a new build?

 

[rpierce]

@rpierce is this a seasoned barrel or a new build?

this barrel has like 300 rounds down it.

 

[rpierce]

So Ryan at 580 yards how would you pick this out? It all looks like the winner to me. I would pick either my higher for hunting or low for a little more brass life.

Nahh high velocity all the way.

Im probably gonna go with the 90 gr charge. The lower nodes have significantly less throat erosion and shoot in all conditions. My retumbo load at 2950 fps only has .003 throat erosion every 100 rounds.