Stock Rifle HV "HOW"

[vzerone]

Another thing with that smooth no lube groove PC'ed bullet is it would have too much bearing surface and much more friction. Barnes changed their copper solids from smooth to ones with grooves to decrease the fouling and friction.

[popper]

I have the 31-165 with and without L.G. both shoot well @ 2400 from 16" & 2700 from 24" upper (1:10 both) PCd (same load, different upper). Vz's pics explanation is correct for 1R, FP boolits, kinda fails for L.G. boolits, #4 COULD happen to a 7-8R boolit, but the pic exaggerated a lot. Let's not get carried away with the RPMTH, as stability becomes more aerodynamic after the boolit leaves the bore, crossover between spin & aero depends on fps, profile, damage due to firing, etc.. Conclusion from Army spark range tests show a 'perfect' boolit exit, way UNDERSPUN is rapidly aero stabilized, i.e., POI = POA by 100yds. I am also beginning to believe that the RPMTH is more an effect of material tensile strength, not imbalance. I.e., spin balance a tire and the middle 'grows' in dia.. Spin it at 140K-200K RPM and see what it does.

[vzerone]

I have the 31-165 with and without L.G. both shoot well @ 2400 from 16" & 2700 from 24" upper (1:10 both) PCd (same load, different upper). Vz's pics explanation is correct for 1R, FP boolits, kinda fails for L.G. boolits, #4 COULD happen to a 7-8R boolit, but the pic exaggerated a lot. Let's not get carried away with the RPMTH, as stability becomes more aerodynamic after the boolit leaves the bore, crossover between spin & aero depends on fps, profile, damage due to firing, etc.. Conclusion from Army spark range tests show a 'perfect' boolit exit, way UNDERSPUN is rapidly aero stabilized, i.e., POI = POA by 100yds. I am also beginning to believe that the RPMTH is more an effect of material tensile strength, not imbalance. I.e., spin balance a tire and the middle 'grows' in dia.. Spin it at 140K-200K RPM and see what it does.

Yes I exaggerated it on purpose to get the point across.

Now take that next to last statement of yours: "I am also beginning to believe that RPMTH is more an effect of material tensile strength, not imbalance". Think about it, if the alloy isn't up to snuff for the load, that is velocity/pressure the bullet then changes from all the forces on it from what was hopefully a balanced bullet to begin with to an imbalanced bullet.

You know the rpm theory wasn't carved in granite by God on Mount Sinai and carried to the castboolit members by Moses 308 Win. Get the rpm notion out of your heads. If you think that high rpm is going to ruin your accuracy you have failed before you even begun.

[vzerone]

I have the 31-165 with and without L.G. both shoot well @ 2400 from 16" & 2700 from 24" upper (1:10 both) PCd (same load, different upper). Vz's pics explanation is correct for 1R, FP boolits, kinda fails for L.G. boolits, #4 COULD happen to a 7-8R boolit, but the pic exaggerated a lot. Let's not get carried away with the RPMTH, as stability becomes more aerodynamic after the boolit leaves the bore, crossover between spin & aero depends on fps, profile, damage due to firing, etc.. Conclusion from Army spark range tests show a 'perfect' boolit exit, way UNDERSPUN is rapidly aero stabilized, i.e., POI = POA by 100yds. I am also beginning to believe that the RPMTH is more an effect of material tensile strength, not imbalance. I.e., spin balance a tire and the middle 'grows' in dia.. Spin it at 140K-200K RPM and see what it does.

popper you also said this in the post above: "as stability becomes more aerodynamic after the boolit leaves the bore". I do believe you meant to say "as the bullet becomes more stabilized it is more aerodynamic" because "stability" isn't a tangible thing. The bullet, if it's balance and exits the muzzle well, indeed does become more stabilized as the gyroscopic action of it spinning it trying to stabilize it from the yaw it receive when leaving the muzzle. I don't know about it becoming more aerodynamic, but I think you meant it's flying more point on then wobbling.

[popper]

Aero stability trumps spin. Spark test uses cardboard to introduce wobble which damps out -100 yds due to aero. Wobble is same as unbalanced boolit effect.

[vzerone]

Aero stability trumps spin. Spark test uses cardboard to introduce wobble which damps out -100 yds due to aero. Wobble is same as unbalanced boolit effect.

I'm just saying stability has no aerodynamics, a bullet does. Stability isn't a tangible, a bullet is. Basically using wrong nomenclature. Yes it's not going to fly as well if it isn't stabilized or put your way wobbling.

[Harter66]

So we should be able to load a 75 gr RN with a gas check for a 32 acp in a 7.62x54 Mosin Nagant and send it away over a full case of 4895 as accurately as over 6.0 Unique ? It would have to be HT lino I expect .

[vzerone]

So we should be able to load a 75 gr RN with a gas check for a 32 acp in a 7.62x54 Mosin Nagant and send it away over a full case of 4895 as accurately as over 6.0 Unique ? It would have to be HT lino I expect .

Harter I'll have to think on your question. I can tell you my cousin pushed a LEE 130 grain gas check bullet of water quenched 50/50 alloy to over 3100 fps win little over one inch group at 100 yard more then just once. The group had 4 cutting little over 1/2 inch. This was from an AR10 with a 10 twist barrel using a max load of H4198.

Both your loads are attractive and it seems the Unique would definitely shoot well. Problem with the 4895 is that it's slow in comparison of the bullet weight you will be shooting. It may work, but I honestly don't know because I haven't tried that one.

I did know an older gent that use to pull the 90 grain FMJ bullets from 30 Luger cartridges and load them to exceptionally high velocity in his 30-06 Springfield to hunt groundhogs. Didn't matter it was a FMJ bullet it turned a groundhog inside out. Very interesting concept. Thing was like a 30 caliber 220 Swift.

If you load the Unique make sure you hold the rifle muzzle up before each shot to insure the Unique is against the flash hole or it's vicinity.