300 Norma Mag

#301
marzo2 said:
So if I take these numbers, is it possible that is why that I cannot see a mesurement difference when I try to FL size my new Lapua brass?

I have the Hornady comparator (.420) and the Whidden (.450). Mesure at 2.067. Set-up the fl die, run the brass and still get the same mesure, even if I screw the die until I cannot cam-over.., Btw I use Forster did
Click to expand...
Take a piece of your new brass and see if it will chamber in your rifle. If it does (and it should), measure it and record the length with your comparator. Load it and fire it, remeasure with your comparator. The difference between the two will be how much your brass is stretching to fill your chamber. The fired brass gives you the headspace on your chamber. Now when you set up your die only bump the headspace back on the fired brass by .002

You will likely find that the headspace on your new brass is going to grow enough that you will be able to set up your die.

It isn't a bad idea to check again after your second firing and tweak your die set up if needed. Sometimes your headspace might be just a little longer than your first firing and to keep your die bumping your headspace by only .002 you might just have to raise it another thou or two.
 
#302
BClrh said:
Take a piece of your new brass and see if it will chamber in your rifle. If it does (and it should), measure it and record the length with your comparator. Load it and fire it, remeasure with your comparator. The difference between the two will be how much your brass is stretching to fill your chamber. The fired brass gives you the headspace on your chamber. Now when you set up your die only bump the headspace back on the fired brass by .002

You will likely find that the headspace on your new brass is going to grow enough that you will be able to set up your die.

It isn't a bad idea to check again after your second firing and tweak your die set up if needed. Sometimes your headspace might be just a little longer than your first firing and to keep your die bumping your headspace by only .002 you might just have to raise it another thou or two.
Click to expand...


Thanks! Its usualy what I do also. But found strange and its a first time for me, that I am not able to size a new brass in a FL die.
 
#303
marzo2 said:
Thanks! Its usualy what I do also. But found strange and its a first time for me, that I am not able to size a new brass in a FL die.
Click to expand...
You don't want to bump the shoulder back on new brass at all if it will chamber as is in your rifle or it will just have that much further to stretch when you fire it. That can increase the chance of case head separation down the road.
 
#305
Birddog6424 said:
I read some of the comments about Reloder 33. I'm kinda surprised, that folks are having issues with carbon rings. This is my second rifle I've used it in, and I havent had issues with either of them.

Currently on about 200 rounds on my Norma, no visible build up on a borescope. Lucky I guess..
Click to expand...

I just received my AXMC and have shot it 50 times a day in the last three days, 150 total. I have cleaned after each 50 and thought the amount of carbon fouling was normal. I have not seen any abnormalities with "rings." I have never seen them.

I was surprised when I cleaned for copper fouling and the patch was only very slightly blue after the first 50. I guess the better the bbl the less copper fouling.
 
#306
Possible higher pressure in my AXMC upon 3rd reloading round count 100-150......

I have been shooting my AXMC, Peterson brass, Fed match mag primers, 92.6g RL33, with a Hornady 225 ELD Match bullet.
My first 50 rounds were different loads a few .10th up and down from this load with the Hornady bullet and Berger 230's. No signs of high pressure. Realized that the bbl was brand new and I should get used to the rifle and let the bbl break in a little. OK I wanted to shoot steel and after a great group at 100, thought I would have some fun from 300 to 1,000.

Cleaned bbl and reloaded another 50 with the Honady bullet and 92.6g of RL33.
Shot the next day, steel from 300-1,000 and found that I was shooting .8 mils high, adjusted and everything went well. Don't know why the raise in POI. Reloads all seem normal.

Cleaned bbl and load 50 more same load as previous.
Shot 500-1200 yards and was able to move between each target and hit consistently. No POI move or change in DOPE. Wind gusting and changed directions 90 deg.
POI same as previous day but pressures seemed higher. Noticed the primer had a little more of a crater than before and a very slight shinny spot. Less than the pic in post #253 in this thread. The bolt was SLIGHTLY harder to close on a couple shots and never hard to open. I will measure case length and compare to new Peterson brass this evening.

I ran the LabRadar with most of the 150 rounds fired. And the velocities are all pretty close. Most of the increase of maybe average of 50 FPS faster happened in the 50 shots. No difference in the last 50 from the prior 50. My wholesaler was out of the 8lbs keg of powder so I bought 5 1 lb containers. Will check to see if the powder is from different lots.

Any idea why the pressures might be up?
Different lots of powder?
Should I be concerned?
The rifle was still shooting great, at least for me.

LOVE the 300NM round and the AXMC!

Thanks,
Steve
 
#307
using virgin peterson brass on day 1, then reloading it for the next day's shooting? Fire-formed brass will act differently than virgin. My peterson brass is also quite short at the shoulder (i.e. "headspace" measurement) when new.
 
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#309
Stevo3556 said:
Possible higher pressure in my AXMC upon 3rd reloading round count 100-150......

I have been shooting my AXMC, Peterson brass, Fed match mag primers, 92.6g RL33, with a Hornady 225 ELD Match bullet.
My first 50 rounds were different loads a few .10th up and down from this load with the Hornady bullet and Berger 230's. No signs of high pressure. Realized that the bbl was brand new and I should get used to the rifle and let the bbl break in a little. OK I wanted to shoot steel and after a great group at 100, thought I would have some fun from 300 to 1,000.

Cleaned bbl and reloaded another 50 with the Honady bullet and 92.6g of RL33.
Shot the next day, steel from 300-1,000 and found that I was shooting .8 mils high, adjusted and everything went well. Don't know why the raise in POI. Reloads all seem normal.

Cleaned bbl and load 50 more same load as previous.
Shot 500-1200 yards and was able to move between each target and hit consistently. No POI move or change in DOPE. Wind gusting and changed directions 90 deg.
POI same as previous day but pressures seemed higher. Noticed the primer had a little more of a crater than before and a very slight shinny spot. Less than the pic in post #253 in this thread. The bolt was SLIGHTLY harder to close on a couple shots and never hard to open. I will measure case length and compare to new Peterson brass this evening.

I ran the LabRadar with most of the 150 rounds fired. And the velocities are all pretty close. Most of the increase of maybe average of 50 FPS faster happened in the 50 shots. No difference in the last 50 from the prior 50. My wholesaler was out of the 8lbs keg of powder so I bought 5 1 lb containers. Will check to see if the powder is from different lots.

Any idea why the pressures might be up?
Different lots of powder?
Should I be concerned?
The rifle was still shooting great, at least for me.

LOVE the 300NM round and the AXMC!

Thanks,
Steve
Click to expand...
Different lots of powder can have a substantial variance in burn rate. I have seen it on more than one occasion and tested it to confirm.
The other thing I would check for is a donut in your brass. Try sliding a bullet in your fired brass and see it jambs at the neck shoulder junction.
What length of barrel and what velocity are you getting with that load?
 
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#310
Thanks BClrh

I was able to slide a bullet in the empty case, no issues. Didn't see any deformity in the neck.
27" bbl 3020 FPS was the average.
case grew .012" in three firings.
I think I forgot to mention I only neck resized and it was at .338. That was the OD of a new case, so I started there.
 
#312
I am wondering the same. I don't know. I have read, but not experienced , higher pressures when the bullet has no jump.

I have the bbl out and just finished cleaning. I don't have the 300NM comparator case for the Hornady Bullet seating depth measurement so I am placing a bullet in the case and pushing it into the chamber by hand. Just started. I will see if the seating depth I was using took all my jump out after it grew .012....

Thank you very much SAP.
 
#314
SAPenguin said:
Maybe case growth? If the brass is substantially longer after the 1st 2 firings (you say 0.012"), it could "pinch" the bullet in the lead area of the chamber, thereby causing pressure.
Click to expand...

Check into this. Your subsequent post speaking of your COAL does not address this concern. What you need to do is measure your brass OAL. The shoulder gets bumped forward during firing and your neck also gets longer as brass migrates forward from the web. If your brass was trimmed to length or shorter than the trim-to-length prior to your initial firing, it may be well beyond this trim-to-length by now. Comparing your fired brass to your unfired Peterson brass is also largely irrelevant other than for comparison sake. What matters is the length of your brass compared to the recommended trim-to-length and even more importantly the cut of your chamber.

You mentioned the bolt being slightly harder to close but not to open:
Stevo3556 said:
POI same as previous day but pressures seemed higher. Noticed the primer had a little more of a crater than before and a very slight shinny spot. Less than the pic in post #253 in this thread. The bolt was SLIGHTLY harder to close on a couple shots and never hard to open. I will measure case length and compare to new Peterson brass this evening.

Thanks,
Steve
Click to expand...

This may be because your brass is now longer than the chamber is cut for. If it is longer at the shoulder (quite likely since you said you have been neck-sizing with no mention of shoulder bumping) it will make it harder to close the bolt but there will also be resistance when you open the bolt after firing. However, if the neck is exceeding the area of the chamber that is cut out for it, it may be protruding into the throat where it is being squeezed by the barrel (causing the tension you feel) and then your brass is squeezing the bullet which increases your effective neck tension and can cause pressure spikes like you are experiencing.

As for seating depths, touching the lands leads to higher peak pressures as well since the bullet doesn't get a running start prior to hitting the lands. Think of the difference between hopping a curb in a truck when the truck is already rolling versus the truck being stopped and having to power over the curb.
 
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#315
Thanks again SAP and McCrazy,

I have never run into this problem before and I have only neck sized my 300WM and 260Rem in bolt guns, full length size in the gas guns. So new to me. Thanks for the help.

After 3 firings it grew .012" OAL from the new brass.
I placed the fired cases in the bbl and compared to the new brass. Easy to do/see with the bbl pulled. It does look like the fired brass doesn't enter the chamber as far.

I have never bumped necks back. I am pretty sure I am running the brass as far as I can in the neck sizing die and I'm not bumping the neck, so I assume I need to full length resize? If this is the case then I will have a case that is not formed to my chamber the next firing and will possibly change the POI slightly??

I am aware of the higher pressures with the bullet touching the lands. Thought that might be the issue as I didn't know how much of a jump I had until last night when figured it was .1.

Had never considered the increased neck pressure due to the case protruding into the throat. Makes perfect sense to me now. Thank you for taking the time to explain it. Sorry SAP if that is what you were saying and I didn't understand.

I ordered a case trimmer a couple days ago, not here yet. I will trim and see how that effects the fit of the case into the chamber. My GUESS is that it will be the shoulder.

Do I need to full size every so often to bump back the neck? Looks like in two firings for this load.
What would you do??

Thank you,
Steve
 
#316
Steve,
To be honest, I used to neck size and then only bump the shoulder when needed but that allows an ever larger variance in your loads and you end up running into bolt closure issues at times. Now, I just bump the shoulder back a couple thousandths and full-length resize every firing.

If I give up any sort of accuracy, it is marginal and insignificant to me. The consistency of having the same reloading process every time and having rounds that are the same every time and properly chamber is more important to me.

If you have a match chamber, the full-length resizing won't be moving the brass very much anyways compared to brass fired in a sloppy factory chamber.
 
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#321
Stevo3556 said:
Thanks,

Ordering a full length resizing die with neck bushing now....

Thanks for the great help everyone!

Steve
Click to expand...

I used new brass and the pressures were high, holes in primes. Shot a Hornady factory round, high pressure and hole in primer.

I started a new thread in the bolt guns discussion forum in the event that this wasn't the proper place to continue with this personal issue.

Thanks,
Steve
 
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#324
BClrh said:
That's not many rounds. Any details? Load you were using, velocity, barrel length. Did you have it bore scoped?
Click to expand...
I shot 84gr of h1000 225eldm and then switched to 86.5 gr of h1000 215 bergers for the rest of the time. Was averaging 3090 with the bergers. Barrel length is 26 inches. Yes I bore scoped it. It looks rough.
 
#325
jaybigboy34 said:
I shot 84gr of h1000 225eldm and then switched to 86.5 gr of h1000 215 bergers for the rest of the time. Was averaging 3090 with the bergers. Barrel length is 26 inches. Yes I bore scoped it. It looks rough.
Click to expand...
That's to bad. With h1000 and pushing 215's at 3090, which shouldn't be extreme pressure, you would think that you would get 900 to 1100 rounds. 650 is less than a RUM usually gets.
 
#326
BClrh said:
That's to bad. With h1000 and pushing 215's at 3090, which shouldn't be extreme pressure, you would think that you would get 900 to 1100 rounds. 650 is less than a RUM usually gets.
Click to expand...
Only thing I can figure is that a shot it pretty hot a few times this past summer in hot weather and that started the process of it burning up quicker.
 
#328
jaybigboy34 said:
Anybody shot one of these barrels out yet besides me? Mine was done at 649 rounds.
Click to expand...

Were you getting the barrel really Hot and not allowing cool down every 5 rnds or so?
Your loads don't seem like hot loads at 84-86grns..cleaning regiment?

Well , 300winnies are only good for about the same when they are runned hot...600-1000rnds
 
Last edited:
#329
Yerman said:
Wait...what. You shot out a 300NM barrel in less than 650 rounds?

Besides the borescope, how was it shooting?
Click to expand...
Not good. I was shooting at 1627 yards on a pretty much windless day at my 24 inch plate and one shot would hit the plate then the next would hit 2 moa in front of the plate. It went back and forth the whole time doing that.
 
#330
wildcats said:
Were you getting the barrel really Hot and not allowing cool down every 5 rnds or so?
Your loads don't seem like hot loads at 84-86grns..cleaning regiment?

Well , 300winnies are only good for about the same when they are runned hot...600-1000rnds
Click to expand...
There were a few times I let it get pretty hot were it was too hot for me to touch the barrel. Not many, may about 5 times, but I guess it only takes maybe one time getting it that hot for it to stop shooting?
 
#331
jaybigboy34 said:
There were a few times I let it get pretty hot were it was too hot for me to touch the barrel. Not many, may about 5 times, but I guess it only takes maybe one time getting it that hot for it to stop shooting?
Click to expand...

The reason i ask it's because a friend of mine ran his 300 Dakota hot many times and after approx.600 rnds the barrel showed alot of errosion and heat cracks for the 1st few inches of the throat area and the last 3 inches of the muzzle end.however last time a shot it,it still printed 1/2 moa at 100 yards for 5 rnds. at 26 inches you can still set the barrel back a couple inches and still get decent fps and barrel life.
 
#332
wildcats said:
The reason i ask it's because a friend of mine ran his 300 Dakota hot many times and after approx.600 rnds the barrel showed alot of errosion and heat cracks for the 1st few inches of the throat area and the last 3 inches of the muzzle end.however last time a shot it,it still printed 1/2 moa at 100 yards for 5 rnds. at 26 inches you can still set the barrel back a couple inches and still get decent fps and barrel life.
Click to expand...
ok thank you. I may look into it again, but it didn't look good the other day.
 
#333
Don't get your hopes up. With cartridges that kill barrels with fire cracking rather than slowly wearing them out, they loose the ability to hold vertical at distance before the 100 yard groups open up much. I'm not sure if they're not engraving the bullets consistently anymore, or just tearing them up. If you had calm conditions and a chrono that verified the velocity spreads you were expecting, that vertical is the barrel going south. It's also easy to write it off to having a bad day, but when was the last time you shanked several shots in a string 2 moa at 100 yards? It just doesn't happen.
 
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#334
The minimum chamber length on the CIP 300 Norma drawing is 2.502"
The maximum case length is 2.492"
The recommended case trim to length is generally 0.010" under the maximum case length. That would be 2.482"
There isn't a SAAMI specification for the 300 Norma.

I'm having the same trouble with the Peterson brass others have reported. It is .006" to 0.014" shorter than my Manson 300 Norma Go Gauge. Norma was .004"-.006" shorter, which is pretty typical for new brass.
 
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#335
SIDS01 said:
The minimum chamber length on the CIP 300 Norma drawing is 2.502"
The maximum case length is 2.492"
The recommended case trim to length is generally 0.010" under the maximum case length. That would be 2.482"
There isn't a SAAMI specification for the 300 Norma.

I'm having the same trouble with the Peterson brass others have reported. It is .006" to 0.014" shorter than my Manson 300 Norma Go Gauge. Norma was .004"-.006" shorter, which is pretty typical for new brass.
Click to expand...
Mine was really short, grew .020 on the first firing, but gave me no trouble and shot well. A couple didn’t want to let the extractor grab them but my ejector spring was very stout. I’m thinking that would have happened on any brass that wasn’t squished into the chamber. I trimmed the spring and it grabbed every one after that. I’m prob going to trim a little more as it still flings the brass really hard. I put a strip of adhesive suede/leather on the side of my action because the brass was beating the crap out of it and chipping the cerakote when the ejector throws it out.
 
#337
SIDS01 said:
The minimum chamber length on the CIP 300 Norma drawing is 2.502"
The maximum case length is 2.492"
The recommended case trim to length is generally 0.010" under the maximum case length. That would be 2.482"
There isn't a SAAMI specification for the 300 Norma.

I'm having the same trouble with the Peterson brass others have reported. It is .006" to 0.014" shorter than my Manson 300 Norma Go Gauge. Norma was .004"-.006" shorter, which is pretty typical for new brass.
Click to expand...
I will never use Peterson brass for my 300norma mag again.
 
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#338
jaybigboy34 said:
I will never use Peterson brass for my 300norma mag again.
Click to expand...

I'm pretty much there too. I'm going to expand the necks to 338 and set up a false shoulder. I might as well be shooting a wildcat.

I haven't done a pressure ladder yet to see if its good for any velocity over the Norma brass, but it'd have to be a bunch to be worth it. I'm not confident, metallurgy seems a lot more complicated than dimensions and Peterson seems to have a lot of trouble with dimensions.
 
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#339
Any one have loads for 200 grain X Lr, accubonds, and or swift a frames? Thinking of taking it on a grizzly, moose, sheep hunt in the fall and want to run a tougher bullet
 
#341
SIDS01 said:
The minimum chamber length on the CIP 300 Norma drawing is 2.502"
The maximum case length is 2.492"
The recommended case trim to length is generally 0.010" under the maximum case length. That would be 2.482"
There isn't a SAAMI specification for the 300 Norma.

I'm having the same trouble with the Peterson brass others have reported. It is .006" to 0.014" shorter than my Manson 300 Norma Go Gauge. Norma was .004"-.006" shorter, which is pretty typical for new brass.
Click to expand...
My recent Peterson brass headspace was 0.014” short of “go” as well. Had to jam and fireform to chamber. Fired brass was “go” plus 0.001” so it doesn’t seem to be a reamer issue with my setup.
 
#342
Does anyone know of a CIP length 300 Norma mag/338 lapua magazine that is made of a polymer or aluminum? I am not digging the half pound steel mags.
 
#343
Im after some help. Ive been through most of the pages here and found a bit of info.
Im getting a 300nm barrel for my AXMC in the next few weeks and im looking to be reloading 230gr bergers and 200gr cutting edge bullets. Lapua brass. One issue ive got is im an the UK so cant get H1000. Ive seen N570 mentioned what other powders are worth looking at and what loads to start and a rough max load just to give me a rough idea where to start.
Hope someone can give me a bit of info
 
#344
Shendy said:
Im after some help. Ive been through most of the pages here and found a bit of info.
Im getting a 300nm barrel for my AXMC in the next few weeks and im looking to be reloading 230gr bergers and 200gr cutting edge bullets. Lapua brass. One issue ive got is im an the UK so cant get H1000. Ive seen N570 mentioned what other powders are worth looking at and what loads to start and a rough max load just to give me a rough idea where to start.
Hope someone can give me a bit of info
Click to expand...
Take a look at the Lapua/VV powder website. They have the exact data you’re looking for.
 
#346
jaybigboy34 said:
I will never use Peterson brass for my 300norma mag again.
Click to expand...

Can someone recommend some brass then? Just purchased a 300 barrel for my AXMC and was looking for Peterson (which I will now avoid) or Lapua but the only brass I can find is Hornady or Norma. I’ve read that these two have a short life spans so now I’m leery on almost all of it.
 
#347
MattWV said:
Can someone recommend some brass then? Just purchased a 300 barrel for my AXMC and was looking for Peterson (which I will now avoid) or Lapua but the only brass I can find is Hornady or Norma. I’ve read that these two have a short life spans so now I’m leery on almost all of it.
Click to expand...
I am on my 8th firing so far with norma brass. It is not near as bad as everyone thinks. Heck it works allot better for me over the peterson. I continue to use the norma in my first barrel. I have also added a second barrel and I have been using lapua brass with it. It's top notch as always.
 
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#348
MattWV said:
Can someone recommend some brass then? Just purchased a 300 barrel for my AXMC and was looking for Peterson (which I will now avoid) or Lapua but the only brass I can find is Hornady or Norma. I’ve read that these two have a short life spans so now I’m leery on almost all of it.
Click to expand...
Also you never know. The peterson may work great for you. It just didn't for me. I pierced so many primers with it that it ruined my firing pin and i had to purchase a new one. I tried different loads. I tried not sizing the case back, and still had pierced primers. I have never had one pierced primer with norma or lapua yet. And I have used the norma many more rounds than I have the peterson.
 
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#349
jaybigboy34 said:
Also you never know. The peterson may work great for you. It just didn't for me. I pierced so many primers with it that it ruined my firing pin and i had to purchase a new one. I tried different loads. I tried not sizing the case back, and still had pierced primers. I have never had one pierced primer with norma or lapua yet. And I have used the norma many more rounds than I have the peterson.
Click to expand...


Thanks for the info!
 
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#350
Hi - I'm new to this forum (1st post), but have been actively reading it for awhile as I experimented with my loads for my new 300 Norma rifle (30" barrel / 1:10 twist). Here are the 2 best loads I have so far:

225gr Hornady ELD Match
86gr Norma 217
30” barrel
Fed 215M
Hornady brass
COAL 3.600”
3,017 fps
0.33 MOA group

230gr Berger Hybrid
86gr Norma 217
30” barrel
Fed 215M
Hornady brass
COAL 3.535”
3,004 fps
0.38 MOA group

I did a step latter from 84gr to 87gr for both the Hornady 225gr and Berger 230gr and it varied anywhere from .33" MOA to 1" MOA. I did a smaller COAL (3.535") to equal the size of the Hornady ELD Match ammo, before measuring for the max COAL on my rifle (3.600") and for some reason, I shot much tighter groups with the Berger 230gr with the shorter bullets. Any idea why?
 
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