338 Norma what am I missing?

[Gilly]

I am trying to make a decision on what chamber to have done on a barrel for my axmc for elr shooting that will increase the range over what I currently have (by enough to reasonably justify it). I bought the rifle with 26" 1:10 300 win mag barrel and working on a load with 215 bergers, I have a little more work to do but happy with results so far. I think I will end up around 2925-2950 which is where my previous 300 win mag was at for velocity. Our usual DA is 4000-6000 so that will go a long ways, I am fortunate to live in an area where I can be shooting 2000+ yards within a 15 minute drive, depending on the conditions the 300 win mag will get there but likely getting to a point it is running out of steam especially on a day like last week where DA was 3500. Knowing the time it takes to get a barrel done and load developed complete I am looking down the road just a little here. I would like something with increased range capability to stretch further and should make it at least more predictable at say 2000 yards if it is still supersonic or top end of transonic range vs the 215 berger load out of 300 WM which is going subsonic at that range on the low end of DA.

The 300 Norma has been on my radar a while, especially if I can get it to shoot the 198 flatlines at the velocity it should be capable, but there are not 9 twist barrels in 30 cal for the AXMC just laying around it seems. The 215 or 230 berger would be 100-200 fps increase over the win mag from the average load I've found vs what I can achieve, not sure that is enough to justify cost of barrel and components as it doesn't extend range by much. Feel free to correct me if I am wrong on this. Although once the win mag barrel has neared the end of its life this looks to be a fantastic upgrade if I am in the position of needing a replacement.

So I started looking back at 338 specifically the norma which I had read about before but never had a platform to where I could go 338 so easy without building a dedicated rifle. I am sure the popular choice is the 338 Lapua but I have read most of the original thread and others on 338 Norma, and it seemed to have multiple advantages at the time. Maybe longer magazines have fixed some of that and made it a non issue. But I still see in recent load data that similar velocity can be reached with either one. Say 2800 with at 300 grain projectile as a goal, both can achieve this and be pushed harder it seems. I read so much about inherent accuracy with Norma, and still read that on the 300 Norma. It is doing this all with less powder than the Lapua case. So why is it so quiet these days on 338 Norma? Occasionally some load data will show up in reloading depot but I feel like I am missing something from 2014 on which maybe was on the scout site and didn't come over. Is there a reason it fell off the radar, or are there still a lot of guys running this case and it just isn't that apparent?

 

[jaybigboy34]

I have no first hand experience, but from reliable sources I have heard that the 338 norma is more accurate than the 338 lapua. How much I have no idea. I am having a 300 norma mag built for myself so I look forward to seeing if it's worth the extra money over the 300wm.

 

[Ankeny]

I hesitate to even post without personal experience. I am trying to decide which ELR build to go with. The high zoot gunsmiths that I have visited with seem to feel the 338 Norma case design is inherently accurate, and loads are easier to develop. Kind of like the advantages of a 6BR case. I hate to show my ignorance, but what is DA?

 

[TripleBull]

I hate to show my ignorance, but what is DA?

Density altitude.

 

[surgeon260]

I am a huge fan of 338 Norma. For a magazine-fed big 338, where you need to restrict COAL to CIP magazine length, it is really hard to beat the Norma. The Lapua has a higher velocity ceiling, particularly when improved, but it needs a COAL of 4+ inches to take full advantage of that additional capacity.

I shoot 338 Norma Improved (as well as 300 Norma Improved), and I have nothing but good things to say about it. Out of a 28" barrel I am shooting 300 Bergers at 2920, 256 Flatlines at 3100. Bergers are 0.25 MOA at 300 yards, Flatlines are about 0.5 MOA. The Bergers are crazy accurate in my rifle. Both bullets are supersonic well past 2000 yards (I am at 6000ft elevation). The Flatline is a laser beam; ~5 mils to 1000 with 300 yard zero. With the Flatlines and a 300 yard zero, I can hold in the reticle at 25x out to 1400 yards without touching turrets. Bullets are seated fully out of the powder column and fit in AICS CIP magazine. Norma brass is excellent and requires no prepping, and Peterson is soon to release top notch brass as well.

If you want a big 338 repeater, the Norma is simply an awesome chambering. With the Flatlines it will be ~4 mils flatter to 2000 than your 300 WM/215 Berger combo, with 35% less wind drift.

 

[McCrazy]

My recommendation would be to go with the 300 Norma Magnum. You would be able to use the Bergers you already have for the 300 Win Mag and have less recoil than the .338s. It would also save quite a bit of expense that the .338 would entail while still getting a significant increase in ability compared to the 300 WM. All reports I have seen have mentioned outstanding accuracy from the 300 NM and you obviously get a lot more projectiles to choose from.

I have a DTA SRS and had a 300 Norma Mag barrel made for it although I haven't shot it yet. It is set up for the 198 grain Flatlines and I expect it to be a great ELR performer. An additional benefit is since it is a switch-barrel system I can seat the lengthy Flatline projos out of the powder column but still run them in the magazine which is meant to hold rounds all the way up to .338 Lapua Magnum. You would have this same advantage in your AXMC if you went with the 300NM or 338NM whereas if you go with the 338LM it is a bit cramped with normal projos and Flatline projectiles probably won't be a viable option.

Hopefully all that made sense...

 

[DAVETOOLEY]

I have a good bit of experience with all the Norma's and the Lapua on the same platform. Here's what I know.
30 cal will always be more accurate than a 338. The 30's have more accurate bullets. Bullets are the foundation of accuracy. Why the difference? That's for a different discussion.
338 Norma has a different recoil impulse than the Lapua. The Norma is more user friendly. Inherently more accurate? No just different.
My favorite, 300 Norma shooting 225's@2900 fps

 

[Supersubes]

I’ll put in my vote for 300 norma. I never had effortless accuracy with either of my 338 LM’s. Good shooters, not great though. So far the 300 norma has shown that effortless accuracy. One caveat. I bought warner’s reamer from JGS. Very short freebore to accomodate the 198. The 198’s will not shoot for me, and it’s not a tuning thing. It’s an 8 twist 4 groove bartlein, so it shouldn’t be a stability thing. I Recently ran the throat out to suit the 225/230 bullets. Shoots amazing.

If I venture back into the 338 bore size, it will be the norma

 

[Clearlight]

Supersubes : I’m hearing from a select few that the 198 is a little picky
regarding bore dimensions , lands / grooves etc . I’m running the 198’s
out of a 9 Twist Maddco barrel with great success ( 300 NM Improved ) .
I’m throated for 215 Hybrids , and having to jump the 198 70 thou to keep
enough bearing in the neck . Haven’t shot them transonic yet , that will happen
in a week or two .

Back to the OP , If you want to really. step up in performance , then a 300 NM
running 215s only a 100 odd fps or so faster is not much better than your WM .
Id vote for a 300 NM or 338 NM running Warner’s or Cutting Edge solids . Just
make sure you get the twist and freebore right if you go the solid projectile route .

 

[Supersubes]

Supersubes : I’m hearing from a select few that the 198 is a little picky
regarding bore dimensions , lands / grooves etc . I’m running the 198’s
out of a 9 Twist Maddco barrel with great success ( 300 NM Improved ) .
I’m throated for 215 Hybrids , and having to jump the 198 70 thou to keep
enough bearing in the neck . Haven’t shot them transonic yet , that will happen
in a week or two .

Back to the OP , If you want to really. step up in performance , then a 300 NM
running 215s only a 100 odd fps or so faster is not much better than your WM .
Id vote for a 300 NM or 338 NM running Warner’s or Cutting Edge solids . Just
make sure you get the twist and freebore right if you go the solid projectile route .

Certain people seem to have success for sure. It would be nice if warner could put out a barrel recipe that works well with them, if there is such a thing. As of now, no special requirements were noted. Im using the very reamer that Warner would use if you had them do a barrel. They emailed me the reamer print and I bought it myself. My issues point towards stability, although certainly I have enough twist. It’s half MOA at 100, one moa a little past 500, and 5 moa just shy of 700. At those same distances(and out to 980), I’ve shot several 3 shot groups sub .2 moa using jacketed bullets and almost zero load developement. Now that I’m throated for the heavy jacketed bullets, i’ll stick with them at least until a barrel switch.

Dont mind paying for the Warner’s, and really like dealing with Dan and crew. Would be great to get them to work.

 

[McCrazy]

Supersubes- good to see you around and sorry to hear about your poor experience with the Flatlines. I spoke with Dan prior to ordering my barrel and I think he recommended the faster of the 2 twists that I was initially considering. I'll get back to you when I can access my email and let you know what I ordered. I also wonder if my smith used a reamer of a different spec than what Warner recommends. My barrel was delayed for a few weeks while they waited for a new Flatline-specific reamer which may have been cut differently than the one you used. I can't remember right now which smith I used but you and I spoke about him as this was happening and I will find his info with the barrel order and get back to you.

 

[Supersubes]

I seem to recall SAC did your barrel. I cant believe you you haven’t gotten it dirty yet, shame on you! Lol

 

[surgeon260]

If you want to really. step up in performance , then a 300 NM
running 215s only a 100 odd fps or so faster is not much better than your WM .

You could always go improved 300 Norma. Mine pushes Berger 230s at 3060 with good brass life. That's a pretty big performance increase over 300WM.

 

[McCrazy]

I seem to recall SAC did your barrel. I cant believe you you haven’t gotten it dirty yet, shame on you! Lol

99% sure you are correct but I can't access my e-mail account from work in order to check at the moment. Try calling him and see what he has to say about his reamer.

I'm just getting around to getting my reloading set-up established in the new house, plus been deploying for 3-4 months a year and then doing the single dad thing. Time is hard to come by but I'm getting there...

 

[Clearlight]

Only 3 shots ( I know ! ) , but at $3 a projectile here in Aus that will
have to do . Don’t have a pic of group but it was around 0.3 . This is
86.7 grains of H 1000 under a 198 , CCI 250 , jumping 0.070 .

 

[McCrazy]

Dug through my emails and if any of you decide to do the 198 gr. Flatlines in the 300 NM, Dan Warner did suggest an 8" twist. The Berger twist rate calculator says 9" is sufficient but Dan said it wasn't (probably largely due to length of the projectiles).

My barrel was chambered by Short Action Customs (solid and responsive customer service by the way) with the new Flatline reamer although I don't know the specifics of it and if there was any difference than what Dan Warner was suggesting.

 

[Dan Warner]

The 9 twist is what we recommend as a minimum for the 198, so it will work. We tested them in a 9 and know that they are stable in the 9. But why be on the edge if you are building a bullet specific rifle? Better to be in the safe window of operation rather than at or near the point of trouble. So, an 8 twist puts you into that range. And as an aside, the Berger twist rate calculator may get you close, but is not always the bottom line when it comes to solids.
'Barrel recipes' are a difficult thing to pin down, as there are a lot of factors that can skew results. Quite frankly, there are so many that one could spend a lifetime at trying to determine the best combination because not all of the factors are constant or linear. However, as we shoot more and listen to the feedback from our customers, we begin to formulate what could be termed 'the gospel'. It is trusted information that is taken into account for exactly what it is and we can begin to see trends in what works and what does not. For example, the 6.5 121 is a bit finicky and is somewhat unforgiving with respect to the market's share of barrels that are out there on today's 'quick fix' guns. It all comes down to bullet fit in the bore at hand. In most cases where someone is having trouble, it is because there is a poor fit and gas is leaking out in front of the bullet. We do have the ability to cater the bullets to the diameter specific to your bore, but we need to have the bore measurements first. If you can send us the slug cut off from the muzzle, we can measure and make adjustments. Most don't have this luxury, but it is feasible. The other potential point of failure is twist. Just because it says it is a specific number, doesn't mean that there is not some error built in. Most buttoned barrels are slightly slower than stamped because of the mfg process. In some cases, this may be enough to put you beyond the minimum twist recommendation.
Aside from going to these lengths, I ask if you have ever heard of ANY other bullet manufacturer publishing 'barrel recipes'? You won't because there is simply too many variables as I suggested above.

 

[Gilly]

Shortly after posting this I was contacted with information on a 1:9 twist 300 Norma barrel for sale that was very low round count for the AXMC platform. With a 30 cal suppressor hopefully near the end of my wait and running the numbers with 215-225 class bullets and the 198 Flatline I took a chance on it and purchased the barrel. I think I can push the 198 without going too hot and have a load that will make 2250 before entering transonic range. After reading the responses from the past few days I feel good about my decision. Although a 338 sometime down the road might be a nice addition. I will be getting a load worked up for the 215 Berger and 198 Flatline first hoping for 3100+ velocity on both of them and looks like 3200+ can be achieved with the 198 where the barrel is 28" in length.

Thanks for the info and good discussion, I hope to find similar success others have had with the 300 Norma.

 

[Supersubes]

The 9 twist is what we recommend as a minimum for the 198, so it will work. We tested them in a 9 and know that they are stable in the 9. But why be on the edge if you are building a bullet specific rifle? Better to be in the safe window of operation rather than at or near the point of trouble. So, an 8 twist puts you into that range. And as an aside, the Berger twist rate calculator may get you close, but is not always the bottom line when it comes to solids.
'Barrel recipes' are a difficult thing to pin down, as there are a lot of factors that can skew results. Quite frankly, there are so many that one could spend a lifetime at trying to determine the best combination because not all of the factors are constant or linear. However, as we shoot more and listen to the feedback from our customers, we begin to formulate what could be termed 'the gospel'. It is trusted information that is taken into account for exactly what it is and we can begin to see trends in what works and what does not. For example, the 6.5 121 is a bit finicky and is somewhat unforgiving with respect to the market's share of barrels that are out there on today's 'quick fix' guns. It all comes down to bullet fit in the bore at hand. In most cases where someone is having trouble, it is because there is a poor fit and gas is leaking out in front of the bullet. We do have the ability to cater the bullets to the diameter specific to your bore, but we need to have the bore measurements first. If you can send us the slug cut off from the muzzle, we can measure and make adjustments. Most don't have this luxury, but it is feasible. The other potential point of failure is twist. Just because it says it is a specific number, doesn't mean that there is not some error built in. Most buttoned barrels are slightly slower than stamped because of the mfg process. In some cases, this may be enough to put you beyond the minimum twist recommendation.
Aside from going to these lengths, I ask if you have ever heard of ANY other bullet manufacturer publishing 'barrel recipes'? You won't because there is simply too many variables as I suggested above.

Dan,
I agree that beyond twist rate, there isn’t much of a recipe from other makers. Lots of personal opinions from various shooters on land/groove profiles of course, that are mostly groundless imo when it comes to jacketed projectiles. A bad shooting jacketed bullet, that’s properly twisted, still shoots at least OK. That window with the solids is just so much wider.

When you guys buy barrels for the 198 in a Norma case(personal guns or spec’ing for customers), what do you order exactly? Maker, land/groove profile, bore dimension, etc.?

I want to shoot your bullet, don’t mind paying for them, and really like dealing with you and your company.

 

[Supersubes]

99% sure you are correct but I can't access my e-mail account from work in order to check at the moment. Try calling him and see what he has to say about his reamer.

I'm just getting around to getting my reloading set-up established in the new house, plus been deploying for 3-4 months a year and then doing the single dad thing. Time is hard to come by but I'm getting there...

I know, just giving you a hard time!

 

[Dan Warner]

I don't want to list barrel mfg names here; I do not want to come off as exclusionary or promoting one brand over another even though the first may be great. Contact us at he shop & we'll gladly tell you what brands we use. By the way, we are happy to use whatever brand you are comfortable with. That said, most any of the quality mfg's are good to go. As long as the bore dims are geometrically consistent from end to end, it should work. Flatlines are designed to work in standard bore sizes. So a typical land groove combination should be say .299 or .300 over .308. It is that last number that is key. If a bullet measures .3080 and the groove measures .3085, the gas is going to get out in front, as I described before. Most mfg's do not show specs to 4 decimal places, but they can hold it.

 

[Clearlight]

Thanks for the info D W . Next 300 NM pipe will be an 8 with less
freebore , but same land / grooves . Sooner than later though I
suspect , too much fun to shoot !

 

[xdeano]

I chose the 338nm several years ago over the lapua. It's provided to be a scary accurate round. If your shooting out past 1000yds, the extra energy of the 300grn bullet is good at seeing impact splash even at a mile. The 300nm wouldn't be a bad choice either, shooting 230s. Projectiles are spendy for the 338s. If i ever did it over again, I'd probably do a 375 cheytac, 375vm or similar. Maybe a 338 snipetac etc. Input costs on a build will be similar for both 338 and 375, the differences will be with reloading costs and suppressors if you go that route.

Xdeano