Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
I'd load up that 85 grain load with the cci250's and run that. 2950 for a 250 is nothing to scoff at.300 Norma Improved
Bartlein 30 1:9 twist
Peterson Brass
250 Atip
CCI 250
H1000
OAL 3.808
82 gr-2866
82.5 2878
83 2891
83.5 2910
84 2919
84.5 2939
85 2950
85.5 2994
86 2998 ejector marks
86.5 3013 ejector marks and stiff bolt.
I changed primers to Fed 215 and got clickers and it increased FPS. I think 3000 fps is the max ceiling for my gun and this powder/bullet combination.
84.5 gr 3004
85 3009
85.5 3050
Go into Options> Loadable Table Settings> Set Loadable Table Step width> User defined>In weight increments. Then you set up in .3 .5 or a grain or what have you. Most of us load into the tenth...View attachment 8085996
I just played around with what mass bullet would work (fill % > 90) with RL26 in .300NM and the best result was 155gr. So yeah, not a great option.
What's the measurement of the base of the fired brass before and after sizing?Running 250 atips with 88.7grs of N568 in Lapua brass I occasionally get a case that is hard to extract. Pressure wise I think I am okay, bolt lift is fine, it's just an issue pulling the bolt rearward sometimes.
When this happened with my 300PRC I swapped to redding type S sizing die to get the case web resized a bit smaller. Well on my 300NM I'm also using a redding type S die given I thought that would be my best chance of preventing this issue.
Curious if the group has any other ideas on how to clean up sticky bolt pull? Is this actually a sign of pressure that I'm missing? Is there a smaller base sizing die on the market I can use to get the web down smaller?
What's the measurement of the base of the fired brass before and after sizing?
So you're measurements are pretty much in line with what mine are with the exception of the virgin brass. My virgin is usually around .579-580 and if yours are .5775 you may be over pressure. I also see die marks on the brass, are you having any trouble sizing? And what is the case growth looking like?Had a chance to take some measurements tonight. For reference this lapua brass with 3 firings, loading up my 4th now.
Measurements:
- fired case .5845"
- reized cases .5835-.5840
- virgin case- .5775"
Here's a pic for reference. I'm taking my measurement roughly .2-.25" up (red arrow) from the bottom of the case, in the area that the die just barely touches. If it matters I'm targeting .002" shoulder bump. Also the resized cases run fine through my rifle with out firing.
So you're measurements are pretty much in line with what mine are with the exception of the virgin brass. My virgin is usually around .579-580 and if yours are .5775 you may be over pressure. I also see die marks on the brass, are you having any trouble sizing? And what is the case growth looking like?
Are you having to trim your brass?Yes over pressure is something I'm wondering about myself.... I've actually loaded up 10 lighter charge rounds to try out in hopes that makes a difference. Yes the case has die marks after sizing but I don't have any trouble running them through the resizing die.
What do you mean by case growth? I'll have to take some measurements to determine this as I'm not familiar with the term.
Thanks
I think the brass is so tough that you don't get the usual pressure signs. I've been doing load development with the 250 gr. Atip and as soon as I get close to 3000 fps I get clickers even though I'm full length resizing. The primers are not overly flattened and only a very faint ejector mark. If I drop down to 2950 or below all is good.Running 250 atips with 88.7grs of N568 in Lapua brass I occasionally get a case that is hard to extract. Pressure wise I think I am okay, bolt lift is fine, it's just an issue pulling the bolt rearward sometimes.
When this happened with my 300PRC I swapped to redding type S sizing die to get the case web resized a bit smaller. Well on my 300NM I'm also using a redding type S die given I thought that would be my best chance of preventing this issue.
Curious if the group has any other ideas on how to clean up sticky bolt pull? Is this actually a sign of pressure that I'm missing? Is there a smaller base sizing die on the market I can use to get the web down smaller?
I think the brass is so tough that you don't get the usual pressure signs. I've been doing load development with the 250 gr. Atip and as soon as I get close to 3000 fps I get clickers even though I'm full length resizing. The primers are not overly flattened and only a very faint ejector mark. If I drop down to 2950 or below all is good.
Ah yes..... My trim length is 2.485". After firing and resizing, it seems like the cases have grown to 2.488-2.490".Are you having to trim your brass?
That case growth is .004-005" more on average than I'm seeing.Ah yes..... My trim length is 2.485". After firing and resizing, it seems like the cases have grown to 2.488-2.490".
With regards to the other couple comments regarding pressure and tough brass I'm primarily using velocity and bolt lift to determine pressure. My bolt lift is fine, nothing stiff that I've noticed and from what I can tell low 2900s is not unreasonable velocity for a 250 out of a 29" barrel. Primers are fine, not flattened and I don't see any kind of ejector marks on the brass.
Hoping to test the pressure theory at the range tomorrow. I've got 10 rounds loaded up with a slightly lower powder charge so we'll see what happens.
85.7 | 86 | 86.3 | 86.6 | 86.9 | 87.2 | 87.5 | 87.8 | 88.1 | 88.4 | 88.7 | 89 | 89.3 | 89.6 | 89.9 | 90.2 | 90.5 | 90.8 | 91.1 | 91.4 | 91.7 | 92 |
2641 | 2707 | 2642 | 2721 | 2704 | 2705 | N/A | 2730 | 2719 | 2742 | 2732 | 2748 | 2751 | 2786 | 2812 | 2818 | 2788 | 2828 | 2823 | 2854 | 2847 | 2844 |
Not bad velocity, RL50 won't compete with n570 but it seems viable. I'm interested in trying some again and seeing how ES/SD's are with some slightly crunch loads.Loaded up some 250 A-Tips with RL50 from 86gr to 92gr in 0.3 gr increments. Started to feel some crunching at 91.1gr, but very little resistance, at 92gr I had to adjust my seating micrometer 2 thousandths.
AI AXSR 27" 1:8" and 338 Ultra SR
Trim Length 2.489
Case volume (fired case, filled to brim): 103.84 gr
BTO: 2.8450"
OAL: 3.6980"
CCI 250
53* F, 21% RH, 28.04 inHg
No pressure signs at 92 gr, Id like to see how much more velocity I can get out of it, but my goal was 2800 fps, and I get that at a pretty low pressure. Whereas, the Berger Ammunition 300 NM 230 Hybrids is 2883fps 19.4 SD (54 rounds fired over the chrono), and I get some minor ejector swipe and flattened primers.
85.7 86 86.3 86.6 86.9 87.2 87.5 87.8 88.1 88.4 88.7 89 89.3 89.6 89.9 90.2 90.5 90.8 91.1 91.4 91.7 92 2641 2707 2642 2721 2704 2705N/A 2730 2719 2742 2732 2748 2751 2786 2812 2818 2788 2828 2823 2854 2847 2844
I wish I could find some n570 to try but all I have is H1000.It depends on the powder. I ran the 250's out of a 26" barrel at 3025 fps with N570 and had no visible signs of pressure.
My biggest problem is I can't ship primers or powder to Alaska.N570 is definitely hard to get, but honestly not as hard as H1000 over the past couple of years. Yes, I know that doesn't help you right now, but my point is that if you keep an eye out, you'll find N570 before any more H1000 most likely. I've been using the notifications at Midsouth, Midway (not best prices), Natchez, and Bullet Central with good results (usually get 8lbs every six months or so).
Does H50BMG work for 250 atips?Well that's sucktacular.
Thanks, that’s reloader 50 from alliant was looking to see if there was difference with Hodgon h50bmg. @Kopfjager1 thanks for the max. That’s too slow.
Where are you in Alaska... I am in SE and ship to my cousins in Washington then run down shoot a match and drop it at AML and ship ot home.My biggest problem is I can't ship primers or powder to Alaska.
I'm up in Kenai. I found a freight forwarder that will ship it but I need to find a few friends that will go in on a pallets worth of shipping. Nice stash by the way!Where are you in Alaska... I am in SE and ship to my cousins in Washington then run down shoot a match and drop it at AML and ship ot home.
I shipped 90lbs home a few weeks ago. A bit went to some friends, but the rest went into my hoarding, Plenty of us have powder and primers for days, we just have a way figured out on how to ship it. View attachment 8097011View attachment 8097012
I believe my buddy Paul might be the terminal manager of Carlile up there in Kenai. If you had someone in Washington you could send powder to when you find it, you could do what I do and it would be super easy to send larger amounts.I'm up in Kenai. I found a freight forwarder that will ship it but I need to find a few friends that will go in on a pallets worth of shipping. Nice stash by the way!
Damn that's a sight for sore eyes. Unfortunately many of my shooting buddies are passing away and leaving behind all of their supplies and guns. So I'm sitting fat on everything but magnum powders. But thanks for the offer and I think I know Paul from when I was in the fish business.I believe my buddy Paul might be the terminal manager of Carlile up there in Kenai. If you had someone in Washington you could send powder to when you find it, you could do what I do and it would be super easy to send larger amounts.
Primers are around, with small being super plentiful in Washington, bit large were allot harder to find a few weeks back. This pic was almost all small primers, after a week of being on the shelf.
View attachment 8097033
If there is anything I can do to help you all get a larger order together don't be afraid to ask.
I’ve been bumping it back .003 or I get the same problem. I don’t know if it’s because of the high velocity or the stiff brass.Having a brass issue that has me somewhat stumped. Lapua brass, I take my initial measurement (SAC comparator tool) with a fired case zeroed out the calipers and try to bump the shoulder back only .001 and the case would be really hard to close and open. But if I bump it back .002 it gets better and .003 it closes and opens no problem. I have never had this issue before with any other cartridge that I load for. One thing I didnt check was a fired case unsized but on extraction has been pretty easy after I got the freebore issue resolved. What do you guys normally bump back to? I also let it sit in the die for a little bit while I lube up the next case, so maybe 3-4 seconds of dwell time in the die to allow for some set back.
@schmi015 just in case...
I run HBMG50 behind the 250 atips. My sd is 10 on 5 shot string, MV is 2820 fps with 87 grains. Get pressure signs with anything over 88.5 grains. Using a magnetospeed. Am jumping .020" out of a 29.5" barrel.
Does H50BMG work for 250 atips?
yep, this is what im shooting... I have a 30" 1:8 barrel, using 88.5gr of N570 and 225ELDM. im getting 3140 fps. this is an amazing 1 mile load. ive had consistent hits at 2200m. I do notice that N570 is very very dirty.Been looking over this thread like crazy and haven't been able to find:
225gr ELD-M
N570
30" 1:8 Bart
AXMC
any one have some good date?
thanks
Followingyep, this is what im shooting... I have a 30" 1:8 barrel, using 88.5gr of N570 and 225ELDM. im getting 3140 fps. this is an amazing 1 mile load. ive had consistent hits at 2200m. I do notice that N570 is very very dirty.
I have shot this combo with H1000, and don't love it. im going to explore with Retumbo soon to see if I can get N570 performance without the N570 grime and dirt!
I would say that I run this load quite hard. don't have serious barrel erosion signs, and im 600 rounds down the pipe now.