I'm developing a hunting load to use in my 308 FNAR rifle that I'm mounting a thermal on and using for pigs and coyotes. After finding out my gun didn't like the Barnes TSX bullets with H4895, I loaded up som 168 Amax bullets with 40 grains of H4895 and went and shot some groups starting .01 off the lands and working to .13 off the lands. To my surprise, the best load was .13 off the lands which made my COL 2.745. The Hornady book shows a COL of 2.8 for this bullet. I've done load development with may rifles but the guns always liked bullets seated longer the COL. Is it dangerous to shoot bullets seated deeper than COL the book lists? I'm only shorter by .055 than I'm supposed to be and seen no pressure signs with the 40 grain charge. The book says my starting charge to be 35.1 and my hottest load to be 43.5 of h4895. Next range session I planned on seeing if I can tighten of the group with different powder charges. Should I stay a grain or two under the max since I'm seating deep. SO far I shot under an 1.5 inches at 200 yards which isn't bad for a semi auto. Thanks for the help.
Loading shorter than COL dangerous?
- Thread starter giannid
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Mikecr
Well-Known Member
The situation described presents no problem.
Books are for the most part meaningless to YOUR finished barrel. There is nothing you can do about that, except to pursue understanding of what you're actually doing. So think about your situation a minute and consider 'what do I expect to happen and how will I control it?.
Books are for the most part meaningless to YOUR finished barrel. There is nothing you can do about that, except to pursue understanding of what you're actually doing. So think about your situation a minute and consider 'what do I expect to happen and how will I control it?.
Lefty7mmstw
Well-Known Member
In your situation I'd say seating slightly deep would actually lessen pressures, albeit just a bit. So no, not dangerous.
The only time seating a bit shorter than listed oal is actually dangerous is in a small capacity pistol cartridge (ex. 9mm luger or 380 acp), where even a bit shorter can cause a marked difference in case capacity and hence pressure.
The only time seating a bit shorter than listed oal is actually dangerous is in a small capacity pistol cartridge (ex. 9mm luger or 380 acp), where even a bit shorter can cause a marked difference in case capacity and hence pressure.
LoneTraveler
Well-Known Member
You usually do not have problems with loading a bullet deeper, Within reason, Until you start compressing powder to tight. Because every thousands you load the bullet deeper into the case than stated O.C.L. should give you a thousands of free bore. Go slow and be careful and safe.
Rich Coyle
Well-Known Member
When I used Barnes LRX 127 the sweet spot was .180 from the lands. Never had a problem.
Rich Coyle
Well-Known Member
I returned from the range a few minutes ago. My objective was to further check for the best overall length. Just to fit the magazine I had to shorten the cartridges .034" from the lands. That made a starting point of 3.400". At that time I did the same thing as this target but stopped at -.050" which made the overall length at the 3.350". The bottom two targets were fired at that length. The bottom right target was fired with different case weights. The heaviest and lightest and one in the middle of the weights made up the three cases for that group. The upper three were fired in round robin. My new cartridge length will have a length of 3.340". That means the bullets are .094" from the lands.
I use 1" "L" for 100 yards, 2" "L" for 200 yards, and 3" "L" at 300 yards. That's the farthest at our range.
