Does anyone have a suggestion for where to start from this number (77gr) for a 220gr SMK? I have quite a bit of H4350, but don‘t want to blow myself up! I will am shooting a 26” Proof Research carbon fiber barrel on an AXSR.
Does anyone have a suggestion for where to start from this number (77gr) for a 220gr SMK? I have quite a bit of H4350, but don‘t want to blow myself up! I will am shooting a 26” Proof Research carbon fiber barrel on an AXSR.
You're just burning up the barrel with that powder. You should be running that 220 around 3100 fps at max pressure with the right powder. Why bother for 300 WSM ballistics?
Totally agree - here are some options to consider....
You have convinced me. Only considered it based on the numbers the user posted above. He quotes 300 ft/sec faster (10gr heavier) than the calculated data.
edit: Here is what scares the crap out on me. Above says 96.1gr Ramshot LRT (2903 ft/s), where another reference says max load is 89.6gr (2929ft/s).
edit: Here is what scares the crap out on me. Above says 96.1gr Ramshot LRT (2903 ft/s), where another reference says max load is 89.6gr (2929ft/s).
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I’m having Bartlein spin me up a 30” 300NM barrel for my AXMC with the plan of using Lapua brass and Berger 245s. Is there a preference for powder? Retumbo and h1000 I assume, but is one better then the other?
N570 is nearly perfect for .300NM across a variety of bullets and will give you a bit more velocity than H1000 and Retumbo, in that order. RL33 is also a good option for the heavier bullets, but it's just a tad on the slow side.
I've had great results with RL33 and 230's. Pushing 3050 with 91.5 gr
N570 is the only powder I would consider if it's available.
3050 fps with Berger 245's.
WHY , to me its like the 300PRC , WHY , its seems NOT right , why go to a 338LM case , only too shorten IT , should be 300LM ?
BECAUSE, it's not a 300 PRC, it was developed before it, BECAUSE, the Lapua case was shortened to the 338 Norma to accommodate longer bullets to fit in the magazines at the time, AND shortly after it was realized that the .30 caliber bullets had higher bc's and less recoil, giving up very little to the 338's at long range.
Can someone please measure a loaded Lapua brass round case neck diameter please? I need to order some bushings.
0.338" on once fired Lapua brass loaded up with a 230gn Berger.
Fritz just chambered my 300 PRC and 33 XC modBB barrels for a AXSR.
Thanks guys. Thats what I had on some loaded Norma brass hunting ammo, but I wanted to make sure Lapua was the same.
Newby here. Just built my 300 Norma
Mausingfield action
Proof barrel 26”
Ag composite stock
Triggertech diamond
Lr customs brake
Been looking for retumbo or h1000 and I might as well be looking for a unicorn. I can get my hands on h50bmg and US869. I know both have a slower burn rate than the retumbo or h1000. My question is where to start for load development. Gonna be using 230gr A-tips. What kind of velocities can I or should I semi expect out of those powders?
Mausingfield action
Proof barrel 26”
Ag composite stock
Triggertech diamond
Lr customs brake
Been looking for retumbo or h1000 and I might as well be looking for a unicorn. I can get my hands on h50bmg and US869. I know both have a slower burn rate than the retumbo or h1000. My question is where to start for load development. Gonna be using 230gr A-tips. What kind of velocities can I or should I semi expect out of those powders?
I know it's not on your list of powders, but another option if you can't find those powders is RL33. I'm getting 3050 fps out of a 27" barrel with single digit sd's.
That’s a hard one to find also. I have on hand 6lbs hybrid100v, 5lbs 4831sc, 1 1/2 lbs reloader 23, 1/4lb h1000, and tons of small caliber and pistol powder which does me no good.
Was just at store and they had ramshot magnum and accurate magpro. Ever tried them? Pros? Cons? You can see?
Are you finding R33 to be dirty? I’m reading of people having to clean every 30-40 rounds.
It’s no more dirty than N570, but I wouldn’t say it’s so dirty that you have to clean that often.
Currently I can’t really find any powder that’s high on the list for 300NM. I found a local guy who has some 33 for sale so I’m trying to see if/how well that would work.
I haven't found that at all. I clean my barrel every 250 rounds, and its not too bad
Been seeing a lot on long jumps with Bergers. Played with seating depths and settled on .090 off the lands and went out to re-zero at 100 today.
Berger 245 EOL
87.0 grs N570
CB0 2.775" @.090 off
Avg Velocity - 2951 FPS
ES - 10 FPS
3 shots on the left and adjusted scope and 2 shots on the right to confirm.
Berger 245 EOL
87.0 grs N570
CB0 2.775" @.090 off
Avg Velocity - 2951 FPS
ES - 10 FPS
3 shots on the left and adjusted scope and 2 shots on the right to confirm.
I'm having the hardest time finding some N570, been looking for months! I do have some IMR7977 anyone have a starting point on 220gr class bullets? QL showing not so great speeds 2700-2800FPS, just looking for some real world data on what to expect if someone has used this combination. Barrel is a 26" Proof, with Lapua brass and 225gr ELD to start.
Howdy folks, has anybody got any recommendations/tips for the recommended jump/seat depth for 250 atips in 300NM?
running a 30" 1/8" barrel with F215GM and N570
I have done some comprehensive testing on the 225ELDM with N570 - I will be sharing that here soon...
/EK
running a 30" 1/8" barrel with F215GM and N570
I have done some comprehensive testing on the 225ELDM with N570 - I will be sharing that here soon...
/EK
I have run N570 in my 338lm worked great. I came across the N568 and thought it was worth a shot. I I ever can get some 245 Bergers hy's I would use N570 for sure.
I've shot the 230 Berger in my 10 twist 300 WM for a while now and it has performed well out to 1250 yards. My 300NM 35˚ IMP has a Krieger 1 in 9 twist. I can shoot either 215 Hybrids or any of the 230 grain bullets as far as I am gonna have room for here without issue. I wonder if the 8 twist in a fast moving 30 will be enough RPM to have sporadic bullets turning to vapor?
I shoot with an 8 twist 28" K&P. I have no issues so far with it shooting the 230s. I have about 400ish rounds through it so far. Nothing special with the gun. Just an RPR with an LRI chambered 300 norma improved barrel.
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Trying to figure out this AXMC Proof Prefit barrel on why I am getting hard bolt lift at times. It would do it probably half the time and getting some ejector marks. Even some of the lighter loads in testing would do this.
Current load is:
Lapua Brass sized .002 from fired.
84.5gr Retumbo, should be well under max
225gr ELDMs at 3.60 COAL would have to check but should be around there
It shoots lights out, have had a couple of groups well in the teens. Had it out yesterday for some longer range confirmation and had no problems hitting 1 MOA targets out to 1k.
Only thing I could think of is the OAL of the chamber is too short from Proof? I had a .243 barrel once that was cut too short for me to shoot the 115gr DTACs and had the throat reamed out and it shot fine with no pressure issues.
Current load is:
Lapua Brass sized .002 from fired.
84.5gr Retumbo, should be well under max
225gr ELDMs at 3.60 COAL would have to check but should be around there
It shoots lights out, have had a couple of groups well in the teens. Had it out yesterday for some longer range confirmation and had no problems hitting 1 MOA targets out to 1k.
Only thing I could think of is the OAL of the chamber is too short from Proof? I had a .243 barrel once that was cut too short for me to shoot the 115gr DTACs and had the throat reamed out and it shot fine with no pressure issues.
I had issues with a die not sizing the body all the way down to the end of the web.
I would take some web measurements and see if your stickers are .001-2 wider then the ones that extract okay. Eventually I bet if is the die on the next firing, all will have issues.
This can happen if the chamber is on the loose end and so is the die
Brass is probably on it's 3rd or 4th firing. Only have used about 30 cases so far for the initial load development and to make sure everything is OK with the load. I checked a sized case with no bullet and it will chamber and extract fine. Die is a Whidden FL Neck sizer. Cases are also annealed after every firing with a AMP.
I never had any problems closing the bolt, empty or a loaded round. Only fired I would get the issue.
I can get the 250 Atips to 2880fps with 88.5 grains of H50BMG powder. It runs best at 2820 and 87 grains. I'm tempted to try some RL50 at 88-91 grains and see if I cant squeeze out a tiny bit more speed out of a 28" barrel. Sorry Im fresh out of RL50 or I'd give it a try. Anyone else ran 250 Atips behind some RL50?
Dad used my 300NM to smoke his bull last week in CO. Shot it at 1080y. 15 degree angle. One and done. Here’s a pic of our shooting position. Bull was shot in the opening below us. 72 and still going strong! Load:
230 Berger hybrid
Peterson brass
83.5 Retumbo
2910fps
SD: 4
230 Berger hybrid
Peterson brass
83.5 Retumbo
2910fps
SD: 4
What are you guys seeing for case growth with the standard 300 NM?
I'm torn between doing a 40 degree improved version or the plain jane with a 20" barrel.
I hate fire forming but if that 20 degree shoulder causes problems I'd like to mitigate it
I'm torn between doing a 40 degree improved version or the plain jane with a 20" barrel.
I hate fire forming but if that 20 degree shoulder causes problems I'd like to mitigate it
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