Found it, I think.
300 Norma Improved 35 degree
Ya, Id say those Atips did very well. Definitely a lot of potential. And they matched the 338 Lapua Improved's ballistics almost exactly.
forum.accurateshooter.com
Which big 30 to build???
- Thread starter bobinpa
- Start date
Ledd Slinger
Silver $$ Contributor
There are many different drawings as “improving” really just means increasing case capacity. I have seen people improve the Norma shoulder to 30, 33, 35, 37, and 40 degrees. Some with the same body taper, some with less making the body straighter. Also many different freebore lengths depending on what bullet a person has in mind to shoot. Different neck and throat diameters and as well. All resulting in case capacities around 107-110gr H2O.
Haven’t heard of any improved designs that didn’t shoot well. The 35 degree shoulder seems to be a little more popular as it adds a good amount of case capacity and still allows good mag feeding and consistent shoulder bumps when sizing. But deciding on the bullet you want to use that will work for the ranges you plan to shoot is pretty much the biggest decision as that will determine the freebore you need for any given improved design. Also need to make sure that the design is properly specd for either Lapua or ADG brass. Do not use Hornady or Norma brass as the primer pockets will fail long before you ever reach max speeds.
Alex Wheeler already has dies made and available for his design so that takes a lot of time off the clock to get you shooting quicker
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tom
Gold $$ Contributor
And the multiple reamers and barrels wasted while trying to figure out how to not get "clickers" about the 4th or 5th firing! Lol
Most all 30s that have ever existed can tune up and shoot small. These modern rimless cases that have good brass available are all plenty of gun.
Tom
I am certainly leaning towards Mr. Wheeler’s design 35 degree. Really interested running 230gr Berger’s with Lapua brass provided there won’t be any OAL or feeding issues from an AI mag.
Ledd Slinger
Silver $$ Contributor
I originally planned on shooting the Berger 230s but found better accuracy with the 215s. Tho I changed to the Berger 220gr LR Hybrid this year. The 220gr has the same BC as the 230gr but you get faster speeds on par with the 215s.
Dont know if it matters for your purposes, but the terminal performance of the 220gr on game is one of the best I’ve seen with Berger bullets. I have been using various Berger bullets on game for almost 15 years now in 6.5, 338, and 30 cal so I’ve had a ton of experience seeing them perform on pronghorn, deer, elk, and bear. The 220gr LR Hybrid gave a really impressive performance for me and my family this year in my 300 NMI while taking 3 mule deer bucks at 370, 650, and 840 yards. Flawless penetration and exit that minimized meat damage and completely obliterated vitals.
.225” freebore is perfect for the 215gr and 220gr, and will work fine with the 230gr. Can go .235” fb but I wouldn’t go more than that so you can keep your options open. .235” will just barely work for the 245gr after the barrel is broke in. If you open the freebore for the 245s or Hornady 250s initially, you’re kinda stuck with those bullets.
Might be tough to come by right now but Vihtavouri N570 is one of the best powders for the 300 NMI. Gives amazing speed with 215gr and anything on up the ladder in weight. H1000 and IMR 7977 work well for lighter bullets up to 215gr but from 215gr and heavier, those powders won’t match the speed of N570 before pressuring out. RL33 works good for heavier bullets but it’s one of the dirtiest powders I’ve ever used and still won’t match N570 for speed. IMR 8133 is good for speed but I could never find a good tuning window with it. Both IMR 7977 and 8133 seemed to be very touchy and wouldn’t ladder test well for me.
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300NMI with 230 OTM’s (Alex’s reamer) COAL touching lands is 3.573”.
Did you end up around the same charge weight with the 220’s as you did with 215’s? I may give these a try if I can’t get the 230’s up to the speed that I’m hoping for. That’s awesome news, thanks!
Ledd Slinger
Silver $$ Contributor
Pretty much yes. My barrel was going thru the settling period when I was trying to push the 215s up to speed with N570 so I was getting erratic speeds. Would get some at 3240 fps, then they would drop all the way back down to 3180 in the same group. Had good accuracy with consistent speed using 92gr of N570 at 3140 fps with the 215. The same charge weight of 92gr yielded 3175 fps with the 220gr but the testing with that bullet was after my barrel sped up a bit and settled out. I pushed the 220 up to 3204 fps but had a couple jackets separate in mid flight right before the target at 635 yards. My 1 in 9” twist is torquing them really hard at those speeds. I was very close to max pressure at 3204 because a couple had slightly harder bolt lifts and primers were starting to flatten. Backed the load off to about 3185 fps and that was the load we shot the 3 mule deer bucks with this year.
The 220gr is all I ever plan to shoot with the NMI from here on out so a 9” twist is not needed. I have a Hart 1 in 10” barrel on hand that I will use once my Proof CF barrel has run its course. I will push for max speed in the new 10” Hart and I should be able to get up over 3200 fps with the 220s without excessive jacket stress. Even with a 230gr, I would only do a 1 in 10” twist barrel with what I know now about the speeds the NMI is capable of producing. I don’t like over stressing jackets.
I also got the 245gr Berger up to 2990 fps with N570 in my 26” Proof barrel and did not hit max pressure. Accuracy was erratic on ladder tests and I was running out of time before the fall hunting season so I hunted with the 215gr at 3140 fps that year. Never went back to the 245 because later the next spring the 220gr came out. The 220 isn’t really more accurate than the 215 in my rifle, but it flies a little flatter and terminal performance on game is better.
My first 300 NMI before this one was a single shot Defiance Deviant Tactical with a heavy target 30” Broughton barrel but I never tried the 220gr in it because that bullet wasn’t on the market at the time. I had the 230gr Berger and 230gr Sierra up to 3080 fps with good accuracy but couldn’t continue because the Peterson brass I was using was cracking on the body and failing after the 3rd firing. Couldn’t get my hands on Lapua brass at the time and couldn’t safely continue with the failing Peterson brass. While wondering what to do, I decided to sell it and build a repeater NMI I could pack and hunt with.
After witnessing how well the 220gr performed on game, the speed I can achieve with them using N570, and how well they fly in the wind and on cold bore first round shots, I’ve finally found the combination I like in the NMI.
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Ledd Slinger
Silver $$ Contributor
I will add that nobody should take my comments about erratic accuracy with bullets or powders on ladder testing to heart because I also had some erratic accuracy on initial ladder testing with the 220gr and N570. But I kept playing and found the cure
I had been using Federal GM 215 Match primers and they ladder tested excellent with the 215s so I continued using that primer on everything. When I was just about to give up on the 220gr, I swapped to the CCI 250 primer and you could stack 3 shot groups on top of each other at 635 yards over a .6gr spread. Tuned them in with seating adjustments and the ladder test stayed true. So if you ever find yourself in a pickle and scratching your head about what to do with an unsuccessful ladder test, the best advice I can give is to try swapping out the primer. It just might dial it all in for you.
I never went back and tried the CCI 250 on other bullets or powders because I am perfect happy with everything about the performance I am getting with the 220gr. A primer swap on the other bullets or powders could have been the cure as well.
I had been using Federal GM 215 Match primers and they ladder tested excellent with the 215s so I continued using that primer on everything. When I was just about to give up on the 220gr, I swapped to the CCI 250 primer and you could stack 3 shot groups on top of each other at 635 yards over a .6gr spread. Tuned them in with seating adjustments and the ladder test stayed true. So if you ever find yourself in a pickle and scratching your head about what to do with an unsuccessful ladder test, the best advice I can give is to try swapping out the primer. It just might dial it all in for you.
I never went back and tried the CCI 250 on other bullets or powders because I am perfect happy with everything about the performance I am getting with the 220gr. A primer swap on the other bullets or powders could have been the cure as well.
Ledd Slinger
Silver $$ Contributor
I had an AI mag bottom metal to start on my current NMI. They are nice if you really need 5 rounds in the bottom but the Wyatts Center Feed Extended mags with BDL bottom metal feed so fast, smooth, and flawlessly compared to detachable mags it will blow your mind. Downside is you can only fit 2 of the fat Lapua size rounds in the Wyatts CFE boxes. But I just put a two round side saddle on the stock in front of the ejection port so there’s a couple extra at the ready if I need them.
Ledd Slinger
Silver $$ Contributor
Here’s a little visual comparison of the Berger 220gr, 215gr and 245gr. Notice that the 220 meplats are tipped from the factory.
The same 3 bullets from left to right.
220gr, 215gr, 245gr
Notice how the length and bearing surface of the 220 is basically the same as the 215
The same 3 bullets from left to right.
220gr, 215gr, 245gr
Notice how the length and bearing surface of the 220 is basically the same as the 215
Orr89rocz
Silver $$ Contributor
Do they frag After a few inches penetration like the hunting vld designs?
Ledd Slinger
Silver $$ Contributor
Yes, but they stay together better and don’t create as big of an entrance or exit as the 215gr so there is less meat damage.
I shot my buck at 650 yards in the chest as he was quartering really hard towards me. Bullet entered the front of the chest by the right front leg, traveled thru the vital cavity at an angle and exited in 3 holes back behind the left side of the rib cage, each about the size of a quarter or smaller. I found the jacket of the bullet perfectly pedaled out underneath the hide in the middle of the exit holes with no core. So the jacket opened nicely like a flower just like any good hunting bullet does after penetrating and traveled straight all the way thru the entire body from chest to back behind the rib cage while allowing the core to fragment and create devastating damage.
The buck my son shot was at 370 yards and hit him just above center shoulder on a perfect broadside shot. Buck was dead the instant the bullet made contact and he dropped hard right in his tracks and never twitched a hair. Couldn’t even find the entrance hole until we skinned him out for packing. Even with the skin off we were having trouble locating the entrance hole. Absolutely zero meat damage on the entrance shoulder. Exit was about the size of a 50 cent piece centered on the opposite shoulder with bloodshot around the exit about 5” in diameter so still plenty of salvageable meat. When quartering him out, the air cavity between the shoulder and rib cage on the exit side was packed full of chunks of lung that had been blown out of the chest thru the small hole. Didn’t need to look inside to know that his entire vital cavity was destroyed.
Buck at 840 yards was hit behind the shoulder in the traditional kill zone aim point. Could see the entrance because it hit a rib on the way in but the hole was still very small. Exit was about the size of a 50 cent piece. Buck jumped, fell over, got back up tried to run about 20-30 yards before face planting in the ground.
Entrance of the 220gr is akin to the 140gr performance in 6.5mm but there’s so much more energy that there’s always a pass thru (on big bodied mule deer at least) Wouldn’t hesitate to take a center shoulder shot on a bull elk with the performance I saw.
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Orr89rocz
Silver $$ Contributor
Nice. I used 210 vld hunters and shot my first deer at 470 with them. Clean .30 cal entrance, behind shoulder lung shot barely could see but massive exit, Kinda like a fist or a tennis ball and this is a 300 wsm at 2750’s fps muzzle, so i was like wow what would happen in a big 30 or closer range? My brother shot a buck at 125 with a 308 win with the 168 matchking and it went in super clean couldnt see the entrance but exited like a golf ball, maybe touch more.
Ledd Slinger
Silver $$ Contributor
Yeah that was the type of exits I got with the 215gr but the entrances were about the size of a quarter. The first deer I shot with the 215 was a high shoulder aim point that I like. Definitely lost some meat on the shoulders and front part of the backstraps due to such a violent expansion. So I decided to shy away from high shoulder shots with that bullet. Even with a traditional behind the shoulder shot that I took on a buck at 250 yards, the exit was quite large on the rib cage. Large and violent enough to blood shot some of the meat on the back side of the off shoulder even though the bullet path didn’t even go thru any part of the shoulder.
The 215 works great for killing, but the 220 does just as good of a job with less meat damage.
Another one of my favorites is the Berger 250gr Elite Hunter in 338. Pretty much the same terminal performance as the 220gr 30 cal.
Alex Wheeler
Site $$ Sponsor
Lots of good info on here. The reamer I have released through JGS is a .235" freebore. Its good for 215-230s. If 230s are the main bullet, I would go a touch longer. I do not release all prints as some are works in progress. I dont make anything on the reamers either, so no worries there. Hornady makes my dies, but I dont keep many on hand, just enough for the rifles I build. You can call Ben and order one though. Again, I make nothing on the dies if you order one.
Ledd Slinger
Silver $$ Contributor
Nice thing about Alex’s Reamers is that he has a good “no turn” reamer that shoots excellent.
My reamer is a tight neck .339” so I have to turn a couple thousandths off for brass to chamber. Shoots very well but if I ever had another reamer made, I would go with a no turn design like Alex did because the Lapua and ADG brass neck walls are so consistent that they don’t need turning to be accurate.
My reamer is a tight neck .339” so I have to turn a couple thousandths off for brass to chamber. Shoots very well but if I ever had another reamer made, I would go with a no turn design like Alex did because the Lapua and ADG brass neck walls are so consistent that they don’t need turning to be accurate.
I agree 100% on the info I am leaning a ton. Great stuff here!
Mr. Wheeler is Hornady the only option? Could you or are you able to modify a LE Wilson micrometer seater and perhaps a Whiden sizer and Micrometer seater?
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