Are you going to improve this one or just leave it as a standard Norma?
300 Norma Mag Improved. Follow along!!!
- Thread starter Huntnful
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Huntnful
Well-Known Member
It's improved as well. That's just a standard Norma case I was using to get COAL measurements with while the weather is bad haha
Slipping in a highjack of sorts, but if you don't ask - you don't know. In your opinion - what are the pros/cons to AI over standard 300 Norma?
Slight gain in powder capacity but the main benefit is little to no case growth so less trimming and less working the brass to fight growth.
Rick Richard
Well-Known Member
And the con would be the fire forming process. Cost for components and do not forget the extra barrel wear.
QuietTexan
Well-Known Member
Those "cons" are an internet myth - fireforming loads shoot just fine. I have no problems at all taking them past 1k yards. You don't get the full benefit of the modified chamber on the first firing, but you give up nothing on an unmodified chamber either. I hit 300 PRC speeds fireforming 30 SM cases with excellent accuracy, so I'm not sure what the problem is?
Rick Richard
Well-Known Member
To get to the performance level of the intended benefit of the IMPROVED version, you have to do the fire forming regardless If you use standard 300 NM loads. And, yes they can shoot really well, but not the ultimate end as to why going to the Improved. So, I still stand by my Con post or otherwise why do the Improved. Been there done it.
QuietTexan
Well-Known Member
Right right, because heaven forbid the first shot be "just as good if not better than the unimproved" so the second thru forever-est shot will be better 
What you're saying is you'll accept fireforming load performance every time, because you can't get better results the first time.
Even brass in unimproved chambers performs better after at least a single firing.
What you're saying is you'll accept fireforming load performance every time, because you can't get better results the first time.
Even brass in unimproved chambers performs better after at least a single firing.
Meh, Fireforming doesn't bother me. On most big magnums like this, they aren't shot a lot anyway, at least as a hunting rig.
The 300NMI is so easy to tune that I use fireforming loads for group tuning a bullet. Once it's formed and on its second loading usually only minor tweaking is required.
I would venture to say unless someone pushed a 300NMI REALLY hard, 100 pieces of ADG brass would be all they would ever need to buy and 200 rounds would last most hunters a LONG time.
Rick Richard
Well-Known Member
I agree, but don't like using those extra components for fire forming especially when they are so difficult to obtain.
COBrad
Well-Known Member
I bought Whidden's hydro forming die for my 300 NMI. They still need a final fire form but they were also shooting half minute in calm conditions on my 1320 yard range.
Huntnful
Well-Known Member
These dudes all nailed both the pros and the cons.
I will say one con I underestimated is that the brass really takes 2 firings to actually form well to the chamber. So I have Ty form my first 100 pieces in his forming chamber. And then I'll fully form them with a higher charge in my actual chamber
I will say one con I underestimated is that the brass really takes 2 firings to actually form well to the chamber. So I have Ty form my first 100 pieces in his forming chamber. And then I'll fully form them with a higher charge in my actual chamber
I hear this all the time. I'll have to measure shoulder datum to see how much merit there is to that.
MallardAddict
Well-Known Member
I got lucky on my fireforming as I got 5 lbs of R50 for dirt cheap and had 300 old 130gr speers from a garage sale that I used. R50 never seemed to heat up the barrel when forming.
