I have an AXMC with the factory 300nm barrel, which is a 1:10 twist. It shoots lights out with the 225 eldm's. 84 gr of h1000 and .010 off the lands.
Yeah maybe . They’re not running crazy fast , around 2930 ish same as the 230’s . Berger bullets are
non - existent in Australia , so I’ll just have to run with the 225’s for now . I have a feeling they might like
a jam , but that’s a retune , and barrel life is too short to bother with that .
R33 wasn't widely available when I had my norma so I ended up using AR2225/Retumbo. Had very good results, 84.5gr of Retumbo got me 2920fps (SD = 6) with the 230gr Berger hybrid target projectile out of a 28 inch 9 twist Bartlein. Unsure of what barrel life would be as the rifle is now sold, but I'd anticipate it would be slightly better than using AR2217/H-1000. I don't have enough experience to be confident in that statement though.
I've been working on developing a load for my .300NM, and this is what I've come up with:
- 230 Bergers 0.015" off the lands
- 84.4 grains of Retumbo
- Norma brass
- CCI 250 magnum primers
My barrel is a ~29" benchmark barrel, 1:8 twist. My final velocity is ~2923 fps, with an ES of 12. There were nodes higher, but I ran in to pressure pretty early.
- 230 Bergers 0.015" off the lands
- 84.4 grains of Retumbo
- Norma brass
- CCI 250 magnum primers
My barrel is a ~29" benchmark barrel, 1:8 twist. My final velocity is ~2923 fps, with an ES of 12. There were nodes higher, but I ran in to pressure pretty early.
I'm about to grab some Dies. Any advice? I never use really expensive dies and my ammo has always come out perfect. I use Forster Micrometer seater for 6.5 and love it. I was thinking about grabbing one of those. How about for sizing dies? I was thinking just RCBS? Should I get type S? What size bushing for peterson brass?
I have the Redding and also the Hornady. S types. The Hornady sizes the body much too small and I would not recommend it. If I size it on the Redding and then right again on the Hornady, it is like I'm resizing fired brass again. Works the brass way to much for my liking. Redding for me. I have 336 neck bushing for my Peterson brass. Haven't used my 337 or 335 yet.
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What shell holder are you using? Damn you would think that would be easy to figure out but there is conflicting info everywhere and I can't find anything definitive. Sounds like redding 35 will work but it is almost $15. I'm not super cheap but $15 for a shell holder??
RCBS #48. 5 bucks on Amazon. https://www.amazon.com/RCBS-99248-S...i=AC_SX236_SY340_FMwebp_QL65&keywords=rcbs+48
I also run Whidden - I get more consistent shoulder bumps with Whidden dies vs. Redding dies. I use Whidden for every cartridge I reload for now, and get very good results.
Never tried a Whidden. What noticable differences are you seeing? Enough to do anything for you down range? Or just for piece of mind?. In my post I wrote RCBS but meant Redding. Was traveling and don't know why. Lack of sleep. But I see really good results with half inch 5 round groups on magnums when reloading with Redding dies. I have been using a full size Redding with 336 bushing and can't think of a reason to change . Don't know if I'll get better then that on factory AI and Cadex rifles.
I get a lot more shoulder bump variation using a Redding Type S FL sizer vs the Whidden FL bushing sizer. Mind you, my experience with this has been with 6.5 creedmoor, as I had FL sizers in this cartridge from both companies. Same press, same lube, same brass, same press technique - but more repeatable and precise results with the Whidden. It has caused me to move to Whidden for all my cartridges.
Shoulder bump variations will change the pressure and and thus velocities - an inconsistency in ES/SD will be seen. The greater the variation, the greater the inconsistency.
What's interesting, is that PRS precision rifle shooters seem to not like Whidden dies as they supposedly see more run out from them. I see this posted on PRS/precision rifle Facebook groups (ugh) and here. However, bench rest shooters, such as those on accurateshooter.com, swear by Whidden and think they are some of the best dies - this group of shooters is trying to achieve the goal of ultimate precision.
I've never measured run out, so I can't personally speak to that. What I can say though, is that my most accurate reloaded rounds to date have all been produced with Whidden dies. All of the cartridges I currently reload for have an ES of 15 or less (a lot more factors than just the dies for that, I know), and my smallest groups ever shot were produced by ammo reloaded with Whidden dies.
For me, I have seen a difference and have great success with Whidden dies. However, if something else is working for you, keep using it.
What would be a good top end of the range to test retumbo, peterson, 230 berger, cci 250? 86gr? A little more?
I might have to give that a try. I'll probably burn up one of my .300NM barrels and use up the retumbo, and then swap to RE33 for my other barrel.
Anyone try Bertram 300NM brass? I'd be interested to hear your experiences.
https://bertrambrass.com/product/bertram-brass-300-norma-magnum-unprimed-bag-of-100/
https://bertrambrass.com/product/bertram-brass-300-norma-magnum-unprimed-bag-of-100/
Bartlein 1/9-26”, Norma brass, 86gn. Retumbo, Hornady 225gn. Eld-m, gets me 2980fps.
I could go a bit higher, but I was looking for @ 3000fps. The 100 yd. groups are .5 moa.
I am totally happy with load, and I have a ton of Retumbo.
Out of curiosity, does anyone see pressure signs on hot days with RE33?
I could go a bit higher, but I was looking for @ 3000fps. The 100 yd. groups are .5 moa.
I am totally happy with load, and I have a ton of Retumbo.
Out of curiosity, does anyone see pressure signs on hot days with RE33?
I'm getting so done with Retumbo. I had a killer recipe that's been great up until this summer. 86.5 grains in Norma brass with 225 eld-m's. CCI #250 primers. Velocity in the 3040 range with no signs of pressure. As summer has progressed, the load has been getting hotter though and yesterday I could hardly open my bolt. It was 84 yesterday with some humidity, but I didn't think it would climb that much. I'm also done with Norma brass. I just prepped 250 rounds of Peterson brass and I'm starting load work up all over with Reloader 33. I'll post progress later.
I've had nothing but success with Peterson brass and Retumbo but it looks like RE 33 is what most folks are going to . I have a great load with the 225s and H1000, is not fast at 2950 but single digit ES and very accurate.
I couldn't get retumbo and 225eldm to shoot at all for me. I switched to h1000 and it was night and day difference. Now I'm trying 215 berger's with h1000 but so far the groups are not good.
Starting to order components now while my barrel is getting spun up. Going to use the 230 hybrids but reading through the thread it seems like people have switched from H1000 to re33. Is this the consensus now for the 230 hybrids for what I should order?
I'm at the range now letting my barrel cool. It's hot and humid again today and the RL33 is looking much better. I started at 90 grains and went up to 94 by 1gr. increments. Primers just started to flatten out at 93gr. Still no ejector marks. Great accuracy at 92 and 93. Haven't put the magnetospeed on yet. Just trying to check pressure and find a node.
Asking you as you have tinkered with these a lot. Would you recommend .250 freebore for 230/215 hybrids? What approximate OAL would that put the 230s?
Do we agree that this chart is incorrect for retumbo? How about RL33? This is way off from what most here are reporting.
Its way off for me. I'm pushing 2940 with 83.6 GR of Retumbo and a 230 Berger Hybrid. I get stuck cases, hard bolt lift and a bunch of other pressure problems if I go north of 85 grains. Accuracy is good, so far around 1/2 moa out to 600 yards. This is with Norma brass which only seems to last me 3 loadings max before its smoked. I just got 100 cases of Peterson in the mail today which I'm going to do a whole new workup on with RE33.
It's way too hot for me as well. I'd like to know what reamer the Berger guys were using to determine these numbers. I'm at 86gr of RE33 with a 215 moving at 3120fps from a 27" Bartlein barrel. 94 grains?!? I'd blow my gun up.
What headspace competitor size would be used for 300 Norma? I have the hornady tool just need a correct size insert to measure.
Just did some experimenting with Reloader 33 this morning. 90 grains got me 3012 avg with a 230 Berger. I maxed out with pressure at 93 grains and almost 3100 FPS. 1x Norma brass, 28” bartlein 9 twist. So far the powder seems promising. Prior to this I was only getting 2920-2940 ish with H1000 before major pressure, same with Retumbo.
Finally got my hands on some RE 33 , 93 grains made 3100+ with 230s in a 26" 8 twist barrel in my DTA
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Deleted member 110994
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Have you had good luck with the 230 SMK? I'm just starting load development with the 230 SMK, Norma brass, and Retumbo. Defiance Deviant, 27in 1 in 8 Bartlein.
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Primers were pretty flat , no ejector marks and easy bolt lift . Peterson brass is very strong and I'm thinking it may not show pressure until it's really over pressure.
I have a 28" heavy palma bartlein 1:9 being spun up now for a mausingfield and have a stock question. Since I have not shot a 300 norma yet I was wanting some advice. I am going to get a manners t4a but would it be better to get the standard over the elite fill for weight for this round? I am not planning on carrying it through the mountains that I know of and will mostly just be steel between 1-2k use.
Get the elite T4A. The carbon fiber shell makes the stock stiffer than their standard fill fiberglass stocks. Stiffer = more accurate. With a good brake (like the Area 419 Sidewinder) recoil won't be a problem at all.
I am ordering a manner's stock with the mini chassis. Are most people running CIP length mags? I think you have to order the mini chassis different if you want to run CIP. I am ignorant to long action stuff so if I have to order it CIP does that limit the use of most all the rest of long action calibers?
You can run standard SAAMI Lapua AI magazines in a 300NM. But in my opinion CIP mags are much better as they allow you to seat your bullet wherever you need to. I've owned several 300NM and the CIP mags are definitely the way to go. Call Manners and tell them what you want. They'll get you squared away.
Trying to come up with some load tests without testing too high and having to pull bullets. I’ve got RL 33, retumbo, berger 230s, and ELD 225s. I’m thinking top load of retumbo at 86gr and top load of 33 at 93gr? Thoughts or suggestions? It will be with Peterson brass and rock creek 9 twist.
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New to the 300 Norma, but have come up with a load that is very promising.
230 gr SMK .040 off the lands
Norma brass neck turned to .015... I was getting donuts at the neck/shoulder junction
.002 neck tension
85.7 gr Retumbo
Fed 215
Shoots .3 or better at 100
SD of 3
ES of 6
My Magnetospeed said 2982 average out a 27 in Bartlein 8 twist Sendero, drop date increased velocity to 3042. Dialed 4.4 Mils for 825 yards and was high, so I came down to 4.2 Mils and shot a 5 shot group that was 4 inches wide and 1.5 tall... This is the first time I have shot it at anything over 100 yards. 825 was the farthest I could go for now
View attachment 6943757
230 gr SMK .040 off the lands
Norma brass neck turned to .015... I was getting donuts at the neck/shoulder junction
.002 neck tension
85.7 gr Retumbo
Fed 215
Shoots .3 or better at 100
SD of 3
ES of 6
My Magnetospeed said 2982 average out a 27 in Bartlein 8 twist Sendero, drop date increased velocity to 3042. Dialed 4.4 Mils for 825 yards and was high, so I came down to 4.2 Mils and shot a 5 shot group that was 4 inches wide and 1.5 tall... This is the first time I have shot it at anything over 100 yards. 825 was the farthest I could go for now
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Is anyone doing case prep on a dillon 550? If so what shell plate are you using? 300 norma is not listed on there chart and when I called to ask they said they dont have a case to try it with but the 338LM might work.
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