300 wing mag 250 a-tip loads
- Thread starter Schw15
- Start date
Hello!
My first post on this site and im also trying to find load data to 250gr a-tip for 300winmag, using norma MRP and vihtavuori powders. Anyone have some data?
-Aki
My first post on this site and im also trying to find load data to 250gr a-tip for 300winmag, using norma MRP and vihtavuori powders. Anyone have some data?
-Aki
Didn't Broz on LRO do some load workup for the 250 with n570 in a 300WM? I remember him having downrange issues with it opening up/grenading on elk. I will be doing load workup for the 245 EOL once I get it back from Shawn. Should be fairly similar to the 250, but I'll be hesitant to share any data with it being a +P throated rifle...
You're right, it was the 230s he ran and had some issues with. I do remember him giving some loose velocity numbers for the 250 though saying it would likely run in the 2750-2800 range in his rig..? That 245 should be fun to play with though. I'll be excited to run through a few elk, see if the winny can step up to the RUM plate with that +P
First test done with 300winmag A-tip 250gr. vihtavuori powder 570. Col:3,77inch and 76gr powder with fed mag primer. With chrony i got 2637fps. No pressure signs so have to add little more powder to see how much can get speed.
Does anyone have any load data for the 230 or 250gr A-tips in 300WM? I have several powders that are low on the burn chart, and have tried a few with some success. But with the current supply and demand issues, I'm trying to conserve what supplies I have. I have used H4831, IMR-4831, IMR-4955, IMR-7828 and RL-22 with the 230's; and N560(no 570 avail)), IMR-8133, and IMR-7828 with the 250's in my RPR. Although I jumped into the LR sport late in life(2+ years), I feel I've learned enough to jump on here and be able to converse intelligently.
Wow, tough crowd. Am I in the wrong class? Lol. I'm thinking I made a newbie mistake, should i have posted help request on different page?
Have you done anymore testing? I'm happy to share what I have done. New on here. I'm getting 2650fps with 67.5 of N560 through my 26" RPR. <20ES & <10SD let me tag 2 out of 5 sent out to 2000yd plate (last 2). After that milestone, I backed up and began doping the mile plate.
I used h1000 when i had my 300 win. 245 bergers i tried id start at 67 grains and work up to 72 max. 230 with h1000 72 grain start max prolly 75ish. I see you dont have that powder but thats what i used. The imr 8133 would work good just add 2 grains more for start loads
Thank you for your interest and help. As for the 8133, add 2 grains to what min load? The H1000? This is the guess work I struggle with because I don't know the formula(if one exists) to powder down or up when the exact projectile is not published.
OK. Sorry for the delay. I've only had time to try the 230 AT's with 75.0(C) of IMR8133 at 2789fps yielding .75minute groups and ES/SD @ 17/7. however, I will be powdering down due to very slight over pressure signs on 50% of the primers. The approx. reduction in speed(2733) should still be plenty to ring steel at the mile plate, which is the end of the trail for this round and me.
As for the 250-AT's, I loaded up 72.0gr of IMR7828 that chrono'd 2756 with a break. However, when I went to send them out to the 2K yard plate, the first 6 were coming out around 2815 with the suppressor, before jamming my bolt on the 7th round and shutting down my fun for the day. I have replaced my extractor, ball, and spring and will powder down to about 2700 with break, as the first 7 rounds sent were all around the plate before things went south(wind's a bitch Lol)
Lastly, I just got in some N570 from an Oct.2020 BO and will start working that up with Kulmalaaki,s advice from above, as well as the IMR8133; both with the 250g A-Tips only. Hope this helped.
Not sure if you saw my last post re 250 AT's. I have gotten in some N570 and wish to start a workup load and am comparing your data to what I have for the 245/3.545 Berger that VV uses (70.5g(2477) - 77.5g(2752). I'm wondering what length barrel your feeding?
IMR-8133 appears amazing for both the 230 and 250 A-Tips.
With my factory 26" bbl on my RPR, the 230's with 75gr. produced 2790fps, 11 ES, and 5 SD on the lab radar, and grouped .82" with 8 shots.
This helped me place 1st shot impact on both 1000 and 1300 yard plates.
The 250A-Tips with 73.0gr. produced 2644fps, 19 ES, and 8.2 SD with 1.04" 5 shot group.
Note: 76.0gr of N570 produced 2720fps, 22 ES, and 9 SD with 1.13" 5 shot group and ( 77.0gr: 2762/26/10 & 1.17"
Hope this helps.
IMR-8133 appears amazing for both the 230 and 250 A-Tips.
With my factory 26" bbl on my RPR, the 230's with 75gr. produced 2790fps, 11 ES, and 5 SD on the lab radar, and grouped .82" with 8 shots.
This helped me place 1st shot impact on both 1000 and 1300 yard plates.
The 250A-Tips with 73.0gr. produced 2644fps, 19 ES, and 8.2 SD with 1.04" 5 shot group.
Note: 76.0gr of N570 produced 2720fps, 22 ES, and 9 SD with 1.13" 5 shot group and ( 77.0gr: 2762/26/10 & 1.17"
Hope this helps.
Likewise. Which primers are you using and in what temps? I'm Curious. I stopped using GM215M and went to the GM210M with other rcipes and my ES shrunk across the board. I work in Florida, average temp is 82
I lose 12fps on average. I dont pay much attention to the loss as I always have my LabRadar with me when banging steel. The fact I can stay supersonic past 1800yds with these 230 and 250 A-Tips is a big help at a mile.
Hi. Yes that is their match chamber / barrel. I’m not sure exactly what the chamber specs are compared to SAAMI spec.
I just loaded up a couple to shoot in my yard to see if I was in the ballpark pressure and velocity wise. Norma cases, GM210M, 75.0 hrs. H1000, 250 A-Tip.
In my 26” barrel REM 783 it gave 2831fps. It gave just the slightest hint of an ejector mark so I’ll back off to 72 hrs. and then do a proper work up.
I just loaded up a couple to shoot in my yard to see if I was in the ballpark pressure and velocity wise. Norma cases, GM210M, 75.0 hrs. H1000, 250 A-Tip.
In my 26” barrel REM 783 it gave 2831fps. It gave just the slightest hint of an ejector mark so I’ll back off to 72 hrs. and then do a proper work up.
I have not and hope no one else has either(blow up). I have decided to stop running the 250's out to trans and beyond due to poor repeatability at a mile, which I attribute to poor stability(1.23) with my 1:9 bbl. The 230's are a bit more stable(1.50) but at rock bottom of Millers chart, and <15% POA-POI. So I am waiting on a new 28" bbl with a 1:7 twist that I hope will help with Repeatability. I went with 1:7 because I have some 240 monolithics I wish to try. They have higher BC(1.115?) and more load data is avail(240 SMK, Berg 245 EOL). I have also come to the realization that Hornady had the (later released) 300PRC in mind for both these rounds, as they both appeared in the 11th edition Horny reload manual under that case, and not the 300WM.
Are those the 241 pva copper bullets? Those are so tempting to run but $$$$. I've done some testing with the 230 A-tip nothing solid for 1 mile yet. I live at 5400 feet so the 1-9 works great for the 230.
Yes those are the ones. LRI is custom throating my new bbl for a COL of 4.110"(?). Hope to have it soon and something proven at 1k before next trip to the mile and 2K plates in a month.
Nice I was so tempted to do the 212 but decided the extra money for me wasn't worth it shooting to 2100 yards. I hope the 230 a-tips work. I'm pretty slow on speed though. Are you running the 241 in a 300 win mag?
The 230!a tip should be excellent at 2100ish, similar speed and BC as a long barreled 338NM with Berger 300’s and it does quite well at that range.
Yes. I also tried the a few of the 212 mono's in my 1:9 tube and they were almost impacting sideway, as evidenced in the holes on paper. Josh over at PVA confirmed that can and will happen. I have 45 of them left as well. as for speed, weren't you using 8133? that and 7828 get me to 2830 and 2850 with a 26" bbl. 3 friends who all run the 110 elite with a 30" are enjoying 3000ish with RL22 and 4000MR
Yes, sorry for the long delay again. This thing called work keeps getting in the way. Yes, I just got the new 1:7 28" bbl and am collecting seating data with different bullets before installing. Working off of Sierra's 240 HPBT load charts.
