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Dirtdigger

Dirtdigger

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and primer creep. I have rearward primer creep. Is this a headspace issue? No signs of pressure, crony speeds are low.

30/06, 57grains Imr 4350,magnum primer,125gr Nosler ballistic tip boattail.
2681 fps (avg)

Thanks, Derek
 
Something seems odd with your load data, it should be alot faster...
 
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I know.

blargon said:
Something seems odd with your load data, it should be alot higher...
Click to expand...

I've been working this load awhile. Velocites are low. Even with another rifle the speeds are the same. With regular primers and 57.5gr i'm averaging 2720fps. I'm wondering if my crony is the culprit. No primer creep with that load and it groups around 3/4". I shoot some factory ammo as a base, they were within 50-75fps of their published data. I dunno:yingyang:

Derek
 
Dirtdigger said:
and primer creep. I have rearward primer creep. Is this a headspace issue? No signs of pressure, crony speeds are low.

30/06, 57grains Imr 4350,magnum primer,125gr Nosler ballistic tip boattail.
2681 fps (avg)

Thanks, Derek
Click to expand...
Dirtdigger said:
I've been working this load awhile. Velocites are low. Even with another rifle the speeds are the same. With regular primers and 57.5gr i'm averaging 2720fps. I'm wondering if my crony is the culprit. No primer creep with that load and it groups around 3/4". I shoot some factory ammo as a base, they were within 50-75fps of their published data. I dunno:yingyang:

Derek
Click to expand...





What factory ammo with a 125gr bullet is shooting 2700??

Your primers could be backing out due to low pressure. I would try another powder or a heavier bullet. If it is heaspace, it should do it with the heavier bullet as well. But I think you are below the minimum load here. 57.5gr of 4350 will push a 180gr bullet over 2750...A 125gr should be alot faster...

I bet if you switch to Varget with the 125gr bullet, your problems will disappear...
 
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Dirtdigger said:
I'm loading 125's, I used Factory 165's to see if my cronograph was reading accurately.
Sorry about the confusion.
Click to expand...

I think low pressure is your culprit...

Try out the Varget and get back to us...:)

Min load is 53.5, max is 57.5, and running at 3400fps...

http://www.nosler.com/?p=15&b=30cal&s=134

Too low pressure can be dangerous too, the powder couuld just ignite in the chamber and blow up...
 
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Sounds like low pressure all right, but you're in the range suggested by Nosler and that's odd. You're also at around 89% capacity so that's good too. I'm thinking either very hard brass or possibly a cool primer, but more likely underweight powder charges. The speeds you're showing indicate considerably less than 57 grs - you should be in the 2800+ range even with a 22" barrel, as high as 2950 with a 24". What are you throwing powder charges with? Check carefully and weigh accurately. A WLR or Fed primer might make a difference if you're using CCI, but something doesn't add up here.
 
O.K., call me stupid but if the brass has been properly sized so the shoulder slightly comes in contact with the chamber and likewise with the head to the bolt face, there should be no primer creep at any presure...no?

If so, could it be possible the die is pushing the shoulder back a little to much and high pressure loads stretch it back out where as low presure loads don't:confused:
 
Tried Different powder

Loaded some Varget: 125gr Nosler BT

1. 2986fps - 55grs
2. 3022fps - 55.5grs
3. 3047fps - 56grs
4. 3086fps - 56.5grs

These are avg's on a five shot strings.

Once again on the slow side, 55.5grs should be at around 3267fps.

Book Values: (With a 24"tube)

Min - 53.5grs = 3171fps
Max - 57.5grs = 3418fps

30/06 With a 21" tube, so I'm expecting to be down in velocity 60-80fps
not 245fps.

Begining to wonder about my chrony?
 
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