I need a little help figuring out what's going on with my bullets. I'm using Hornady SST ballistic tip 130gr. IMR 43gr of powder, Winchester large rifle primers. Everything is well within measurements for length of the bullet and brass. Shoots fine at 25 yards but it starts tumbling before 50 yards. Any suggestions would be appreciated.
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7mm-08 bullets tumbling
- Thread starter William Crisp
- Start date
IMR what? What rifle? I know Hornady makes a 139 gr .284" bullet but a 130 grain is news to me.
I’ve not heard of the 7mm 130’s either.
Mossberg Patriot 7mm-08 youth. It has a 1.9.5" twist rate. Crown looks good. Using imr 4350
Hornady doesn't show a 7mm 130 grain SST. The load for a 139 SST for IMR 4350 is 39.5-46.5 grains, so your load of 43 grains is good there. Could it be that the twist on that short barreled rifle is too slow to stabilize that bullet? Call Hornady, they will help. 1 (800) 338-3220
You shouldn't have an issue that drastic with a 20" barrel even if loading 140's.
Have you tried a lighter bullet, like a 120gr? By "tumbling" I'm assuming you've gotten keyholing on the target at 50 yds? I've seen that when bullets are traveling too slow AND too fast. What you've described doesn't seem probable so it is an interesting issue...
Have you tried upping your charge weight? Too slow and the bullet can destabilize and tumble. I'm not an experienced loader of 7mm-08 so my observations are coming from 30 years of reloading military chamberings, domestic and foreign.
As mentioned before, a tiny defect at the crown can cause this too.
Have you tried a lighter bullet, like a 120gr? By "tumbling" I'm assuming you've gotten keyholing on the target at 50 yds? I've seen that when bullets are traveling too slow AND too fast. What you've described doesn't seem probable so it is an interesting issue...
Have you tried upping your charge weight? Too slow and the bullet can destabilize and tumble. I'm not an experienced loader of 7mm-08 so my observations are coming from 30 years of reloading military chamberings, domestic and foreign.
As mentioned before, a tiny defect at the crown can cause this too.
I have a Mossberg 100ATR, predecessor to the patriot and mine shoots good with everything from 120 SPH to 154 SST, never seen any tumbling issues.
I am betting either the wrong diameter bullet or there is a barrel defect of some sort.
Rosewood
I am betting either the wrong diameter bullet or there is a barrel defect of some sort.
Rosewood
