300 Norma vs 300 Norma Imp

[Mark L]

Roger that!

 

[Alex Wheeler]

I build both. Theres always a little more hassle with improved cases regarding dies but my improved reamer and dies (JGS and Hornady) are both available to the public and they work well together. The improved case is bigger, obviously. But my main motivation with improving the case is case growth. I really hate trimming. I also do not like running bullets much over 3000 fps so for in the improved case I am recommending guys shoot the heavier bullets. If you do not mind trimming and want to push 215s, then the standard Norma will do it just fine or a lighter load in the imp. Or maybe even simpler would be a 300 prc, 30, or 30-28 Nosler. Theres really only one rem clone action I like to use for the lapua bolt face right now so sticking with standard mags is easier in that respect. I went through the hassle of getting the reamer and dies made up and working because I wanted one and I enjoy playing with long range hunting rifles. The vast majority of my work is long range Benchrest however.

 

[L.Sherm]

Do you see any difference in the tune ability of the NM vrs the NMI? Seems like you and Ryan talk alot about the NMI and 30-28 how easy it is to tune. I know my 30-28 has shot everything I've put down it so far pretty good. I'm only using the 215 and H1000 ,570 and Retumbo so far. Only 50 rounds down it so far I slapped it in a cheap SPS stock no beeding or nothing I think even the stock is touching the barrel in one spot. I've got my AG now just gotta get in that stock before i do much else i just wanted to get some brass cycled with the SPS

 

[Alex Wheeler]

I have not owned a standard Norma personally. When you find a combo that works they are all easy to tune. The 30 Nosler, 30-28, and 300 ni all seem to work well with 215s, 230s, and H1000. Heres my opinion on "easy to tune" cases. Those are the cases that someone else has done the work for you, lol. Popular cases with lots of data. When you know what powder and bullet to feed them, tuning is as simple as adjusting powder charge and seating depth. When you have to work from scratch and try 4 different combos to find the right one that groups and gives good ES they get a reputation for hard to tune. I do not think theres much difference in tunability between the 300 norma, 300 NI, 30 and 30-28 noslers as they are all close enough in size to use the same powder and bullet combos and they all seem to respond well to them. One of the hardest to tune rifles I own is my 280ai, took 4 powders to get it happy, now its one of the most impressive rifles I own. If someone had told me to start with rl23, I would be telling you how easy it was to tune The number one reason people struggle with tuning is because the barrel does not like the bullet/powder combo they are feeding it. No amount of tweaking can fix that. The vast majority of these big 30s seem to shoot H1000 and 215/230 bergers, and that makes them easy IMO.

 

[jb1023]

I build both. Theres always a little more hassle with improved cases regarding dies but my improved reamer and dies (JGS and Hornady) are both available to the public and they work well together.

Hey Alex. You sent me the reamer print awhile back and then I moved in other directions but I'm back to the NI. For custom stuff I've only used Whidden custom dies, and have never used Hornday dies at all, but it looks like Hornady has your specs. Would I be better off buying from Hornady or sending in 3 fired cases? How close to reamer spec are the Hornady's I guess is my question? I'm not a comp or br shooter, just want to ensure the dies are not the weak point in my setup.

Also, do you personally prefer solid or floating pilots?

 

[Alex Wheeler]

The problem with dies is they warp in heat treat. They also need to be cut to the correct dimensions to begin with. Then you have someone polishing them..... Go with you ever your comfortable with. A resize reamer, newlon blank, and nitride case is still the best way to be 100% sure of what you will get. I am contracting some very high quality dies for my improved cases, but I dont know if they will be available to the public or not.
I always order a live pilot but usually dont use a pilot at all.

 

[Rick Richard]

Reviving this since I just got this. a Ryan Pierce build.

 

[WeiserBucks]

Looks like a twin to mine from Dallas Lane.

 

[wasskeet]

Highdrum, Rick - what are your opinions on the 300 NMI now that you have had them a while?

 

[highdrum]

300 nmi is a beast. But have a smith build it who has specd his chamber and dies properly. Elex Wheeler or Dallas Lane can both do that. I have 6 warm firings on my brass in a Pierce chamber. Even with a 250$ bullet central "small base" sizing die and having my chamber honed open for the first half inch I'm still getting clickers on mid psi loads. That stuff Ryan advertises for velocity is on brand new barrels and before brass has grown character.

 

[LeddSlinger]

I have built two different 300 NMIs and have components to build my third NMI. Made some tweaks on the chamber design this time around so just waiting on my reamer from JGS to get it done.

The NMI is a very impressive round. I am running the 220gr Berger up around 3200 fps from a 26" barrel using N570. The standard 300 Norma could never achieve that. I am currently using Lapua brass and case life is excellent. Another guy I shoot with occasionally built a big ELR rifle in the 300 NMI with a 34" barrel and can push the Berger 245gr up over 3250 fps.

Also picked up 300 Norma brass from ADG to test in my third rifle when it's complete.

For fireforming you just load close to max data for the standard 300 Norma and shoot. Max load on the standard 300 Norma is a mild load for the NMI.

Very easy to find good accuracy and N570 is an excellent powder for bullets from the Berger 215gr all the way up to Berger 245gr. Amazingly consistent across a wide range of temperatures and weather conditions and shoots very little vertical at long range. There are many others that use N570 besides myself in the NMI with the same results.

The 215, 220, and 230 work very well with about .235" freebore (+/-.010" fb) and a CFE-12 box.
Your reamer will have to have extra freebore if you want to shoot the 245 and not crowd the case capacity. And the 245 is better suited for a CFE-9 magazine due to its longer OAL.

If you want to use a M5 magazine bottom metal, the CIP+ from Hawkins with the long Lapua mags from Accurate Mags will accommodate most bullets and freebore but maybe a little tight for the 245gr.

 

[Huntnful]

I debated this quite a bit. Decided to go with the 300 NMI. Because I figured you pretty much want once fired brass anyways, so might as well improve the whole design while doing so. And also get the barrel tuned up with a slow firing of 100 rounds down the chamber. So you get a sped up barrel, and a better cartridge to start load development with. Just my thinking anyways. A 230 berger at 3100fps or a 199 Hammer Hunter at 3350 sounds pretty sweet haha.

 

[LeddSlinger]

I have not owned a standard Norma personally. When you find a combo that works they are all easy to tune. The 30 Nosler, 30-28, and 300 ni all seem to work well with 215s, 230s, and H1000. Heres my opinion on "easy to tune" cases. Those are the cases that someone else has done the work for you, lol. Popular cases with lots of data. When you know what powder and bullet to feed them, tuning is as simple as adjusting powder charge and seating depth. When you have to work from scratch and try 4 different combos to find the right one that groups and gives good ES they get a reputation for hard to tune. I do not think theres much difference in tunability between the 300 norma, 300 NI, 30 and 30-28 noslers as they are all close enough in size to use the same powder and bullet combos and they all seem to respond well to them. One of the hardest to tune rifles I own is my 280ai, took 4 powders to get it happy, now its one of the most impressive rifles I own. If someone had told me to start with rl23, I would be telling you how easy it was to tune The number one reason people struggle with tuning is because the barrel does not like the bullet/powder combo they are feeding it. No amount of tweaking can fix that. The vast majority of these big 30s seem to shoot H1000 and 215/230 bergers, and that makes them easy IMO.

What Alex said here is true. I tested a lot of powders with my first couple NMIs. RL33, RL26, IMR 8133, IMR 7977, Retumbo and one or two others. Many of those powders proved a little troublesome with tuning on the NMI while also trying to achieve high velocities. Then I finally started testing N570. Fast speeds with no pressure signs were easy to come by with N570 which made tuning at the higher velocity nodes much easier.

If I had started with N570 on the NMI then I would claim it was easy to tune because it is. But when using some of the other powders listed above, it can be as tough to tune as anything else if you are concerned with achieving high velocity like I am. After all, I didn't choose the large NMI case to run bullets at low velocities. I chose it because it can deliver very high velocity with heavy bullets in a compact design that works well in a repeater action. If velocity wasn't a big concern, I would run a 300 PRC or Nosler variant.

 

[wasskeet]

Thank you for the very informative replies! Now, if one would put accuracy first, above sheer speed as the motivation for looking at this caliber - would you still choose the 300 NMI -or- the standard version, or a simpler cartridge as the 300 PRC?(sticking to 30 cal magnums)