.243 65grain Vmax not stabilizing

desjardo

desjardo

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So I hand loaded some 65grain vmax loads for my .243 VTR.
It has a 1:9 1/8 twist, amd 22" Barrel.
I loaded 37/38/39/40/41 grains of IMR 4064.
And all y bullets key holed or tumbled leaving perfect cutout of a sideways bullet and were all over the map.
The COL was 2.565.
Can anyone help me out with what may have caused this?
 
I just did an inspection and there was some brass on the bolt...
Upon doing some reading it sounds common for new remingtons.
 
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That twist rate should easily stabilize 65 gr bullets. Damage to the crown?

As for your loads, why are your starting loads so far below the published starting load of 40.0 grs?
 
No.
Got it from a user on here like new and just started working up loads.
crown looks ok.
I will grab a box of factory loads and see how they fire.
I was at 25yds and was lucky to hit target.
when they did stabilize they were right on one another.
 
Might be a good idea to just try a heavier weight bullet and see what it does....if it too keyholes I think you have a barrel problem.
 
I use 65 gr V max's over Varget and Remington cases, can't remember the # of grains off hand. The rifle is a Win. M-70, 22" barrel. I have not experienced any tumbling issues. The V max's are fairly accurate but 70 gr.Nosler Varmit BT,s are more consistently accurate in my particular barrel.

I would examine your bore real carefully especially the muzzle. And do try some different ammo like you mentioned. It is a matter of narrowing down the possibilities.
 
Stick a bullet in the muzzle and make sure the bullet is not under-sized or the barrel is not over sized. failing that, I cannot imagine what would cause tumbling.

Keep us advised on what you find out.
 
Loads sound fine, if not a little low - around 3000 to 3150 fps.

Stability should be OK with that twist, according to Litz's calculator.

Weird - let us know what you find out.


Your rifle isn't a .308 by chance?:evil:
 
agilent_one said:
Loads sound fine, if not a little low - around 3000 to 3150 fps.

Stability should be OK with that twist, according to Litz's calculator.

Weird - let us know what you find out.


Your rifle isn't a .308 by chance?:evil:
Click to expand...

As Ganderite suggested, a poor bullet-bore fit seems the last cause to explore. Even if it was a 260 Rem, you'd get tumbling. Stranger things have happened.
 
Seems odd. I'm shooting a Savage .243 with a 1:9 1/4 twist and 22" bbl but did not experience the OPs' issues using Nos 70gr BTs' under a charge of 38gr of IMR 4064

Checking the Hornady 8th edition on your 65gr VMax load. It shows;

IMR 4064
Federal 210 Primer
Start - 35.4gr @ 3100fps
Max - 41.2gr @ 3600fps (caution required)
C.O.L. 2.60"

Have you thought of switching primers? Or try seating to the 2.60 instead of the 2.565" your currently using? As suggest, i'd check the crown of the barrel also to negate any yawing effects it may or may-not be causing.
 
Ya, they are chamfered and it is a .243.
Im being told it may be the length is too short causing an incomplete burn.
Ill keep you up to date.
Don't see any damage on rifling etc.
 
Upon further inspection I can see a tiny nick where the neck or head of case would sit when chambered. Its very tiny so not sure if this would effect flight of bullet.
 
ShrtRnd said:
Seems odd. I'm shooting a Savage .243 with a 1:9 1/4 twist and 22" bbl but did not experience the OPs' issues using Nos 70gr BTs' under a charge of 38gr of IMR 4064

Checking the Hornady 8th edition on your 65gr VMax load. It shows;

IMR 4064
Federal 210 Primer
Start - 35.4gr @ 3100fps
Max - 41.2gr @ 3600fps (caution required)
C.O.L. 2.60"

Have you thought of switching primers? Or try seating to the 2.60 instead of the 2.565" your currently using? As suggest, i'd check the crown of the barrel also to negate any yawing effects it may or may-not be causing.
Click to expand...

As of today, both the Hornady and IMR on-line data for that exact bullet shows:

IMR 4064 C.O.L. 2.600"

Starting Load - Grains 40.0 - Velocity (ft/s) 3,415 - Pressure 43,000 CUP
Maximum Load - Grains 43.4 - Velocity (ft/s) 3,698 - Pressure 50,000 CUP
 
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