.308 reloading need some help here..

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Blast2daFuture

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Well I reloaded some 155gr sierra match king hpbt at 45.5gn with imr 4895 and the chart was saying max load is 47.5 at 2897fps well on the chrony I was doing 3235fps which was alot...

my laupa brass fits in perfect in the chamber and i can bring the bolt knob down.. for some reason the norma brass that i resized , well my rifle wont allow me to bring my bolt knob down. but when i bring the bolt back it ejects teh round. I dont seem to understand this one. I can push the round up the chamber and push the bolt in but cant lock it......

thanks,
 
My first question (as a newbie to reloading .308 as well), is are you neck sizing or full lenght resizing?

I would resize both brass cases and see if there are any differences in diameter dimensions .. also measure case length after resizing and trimming both to see if one is longer then the other. I would suspect that if the case wasn't trimmed to the proper length, the case would be too long to allow full bolt closure.

But it would be interesting to see the measurements taken to prove or dis-prove my hypothesis.
 
What's the length of the cases? What's the OAL of the loaded cartridge?
Is the Norma brass brand new? Did you check 'em for length, trim if required and full length resize 'em?
Any bumps on the cases?
"...reloaded some..." You have to work up a load. Not just pick one.
I'd recalibrate the chronograph too. Unless you seriously over loaded the cases, you're unlikely to be getting 338 fps more velocity than the published max.
 
my OAL was 2.775"

the norma brass was used and i resized and trimmed to 2.008 - 2.010..

i measured each time i put the powder in the casing i just got to bring it down alittle.
 
The shoulder on your Norma cases need to be bumped back. Your resizing die just needs some adjustment. Order a Redding Body die and you can run loaded rounds through them to bump the shoulder back without pulling all your loaded bullets.
Your case would have to be seriously too long in the neck (like .050" or more) to not fit your chamber.
If you can seat your bullets out to touch the lands, I would start there for a seating depth.
I agree with sunray that your chrony need some calibration. I can get 3000 fps out of a 155 with 47.5 of 4895, but the rifle shoots better around 2940-2950 fps.
 
That is way too hot, I bet you used the wrong powder or the wrong charge by mistake. I had results like this once and went home pulled the bullets and remeasured and I hadn't adjusted the setting on my powder scale from loading a different powder.
 
martinbns said:
That is way too hot, I bet you used the wrong powder or the wrong charge by mistake. I had results like this once and went home pulled the bullets and remeasured and I hadn't adjusted the setting on my powder scale from loading a different powder.
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+2 on that.

Sierra says that 43.7gr is MAX for that combination.

Start pulling bullets.
 
IIRC the load used by Jensen who produced the ammo for the 1992 Palma Match in Ratton NM was 47.7 gr of IMR 4895. This is a stout load and caused some sticky bolt handles in the NM heat. I would approach this load with caution looking for pressure signs.
I also do not believe velocity=accuracy. Anything over 2800 fps will sent a 155 gr bullet 1000 yards super sonic and poke a hole through the paper.

Blast2daFuture, there is nothing wrong with your dies that an extra 1/4 turn in won't fix. What was the distance from your muzzle to your chrony?
 
The chrony is broken. If it wasn't, the gun would have been, or at the very least it would have been pieces of cartridge you were extracting. Those are 300 Win Mag numbers.
 
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i dont think the chrony is broken...and no the gun isnt broken either..mabie a little recalibrate but was working fine for the previous rounds..i started off shooting .22lr to get it working properly then i started using various rounds with different loads to get some data
 
maynard said:
I think your chrony is a little too close, it should be 10 to 15 ft. or 3-5 m for you metric guys.
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+2 The chrony is too close, I usually put it 15 feet away, it may work for .22 at 1.5M, but the muzzle blast of your .308 can trip up the sensors.

As far as the velocity you have recorded, it is not possible. I use quickload, I have loaded, and chrono'd nearly 100 loads in 10 rifles, and to date I have found it to be a very acurate predictor.

Using quickload the Load you report should give a mvel of 2880 fps, if it is IMR 4895 and 45.5 gn, 155gn SMK and a 26 inch bbl - the pressure is 55,000psi.

The only way I can get a velocity in the range of 3200fps is to model a load which is 120% case capacity, this will generate a pressure of 90,000 psi which is 30,000 psi above the SAAMI cut of of 60,000psi.

Hence I do not think it is possible to load a case to 120% of its capcity, and live to tell us about it.
 
maynard said:
IIRC the load used by Jensen who produced the ammo for the 1992 Palma Match in Ratton NM was 47.7 gr of IMR 4895. This is a stout load and caused some sticky bolt handles in the NM heat. I would approach this load with caution looking for pressure signs.
I also do not believe velocity=accuracy. Anything over 2800 fps will sent a 155 gr bullet 1000 yards super sonic and poke a hole through the paper.

Blast2daFuture, there is nothing wrong with your dies that an extra 1/4 turn in won't fix. What was the distance from your muzzle to your chrony?
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It was 44.8gr/IMR4895, Fed210M primer, OAL 2.80" that Jensen's loaded.

My reference is Handloader Magazine # 152, July-August 1991, written by G. Sitton.
 
RePete said:
It was 44.8gr/IMR4895, Fed210M primer, OAL 2.80" that Jensen's loaded.

My reference is Handloader Magazine # 152, July-August 1991, written by G. Sitton.
Click to expand...

You must be correct. I am going off fading memory. :redface: They say memory it is the second thing to go, but I can't remembers what the first thing is or who said it.
 
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