30 Cal 260's

[groper]

These bullets are nearly 1.9" long and at the velocities that they can be fired at, I am pretty sure an 8 twist is necessary, especially at the extreme ranges for which they are intended......Rich

Send me a schematic or rough drawing of the bullet, and i can calculate exactly what stability will be using mass inertia equations and derived pitching moments in 3D CAD...

 

[elkaholic]

I have some of the 265 wild cat,s and I have a 300 rum with a 1-10 and they shoot just fine they are 1.750 in length I also shoot the 220 hat,s and they are 1.786 both these bullets shoot outstanding especially the 265 wild cat,s in fact my dad shot his deer with a 265 wild cat at 556yrds and it flat out dropped him you will be surprised on what a 1-10 will shot

Have you tried them at 1000 yards plus?

 

[pitbull320]

yes at a 1000yrds they will shoot 6-5" groups I,v found that most bullets that are under 1.825 with a barring surface of .945 or less will shoot out of a 1-10 but you have to push them over 2800fps.I also have shot the 280 .338 wild cat bullet out of my edge with a 1-10 and they are 1.996 and with them I have shot yot,s at 1000+.

I,m also getting ready to test the rmb in the .338 just waiting for kriby to finish my new rifle then I,ll test them in a 1-10 and that includes there big 325gr

 

[Jon A]

That's really odd, the 265 Wildcats would not stabilize in my last barrel which was a 1:9 twist. I ran them well over 2800 fps as well.

Of course, I tested them at sea level. What elevation are you at?

 

[pitbull320]

I test at 4500 to 5800 and the barring surface i put in was a miss tip it was supposed to be .685

 

[elkaholic]

I test at 4500 to 5800 and the barring surface i put in was a miss tip it was supposed to be .685

That bearing surface makes a lot more sense. Mine is somewhere around .8 give or take. I'll get some better measurements tomorrow....Rich
p.s. Also, don't forget the larger the bullet diameter, the less twist you need for the same b.c. (that's why the 300 smk's will work in a 10 twist)

 

[groper]

The altitude difference from sea level to 5000ft will increase the stability factor of these bullets by ~ Sg = +0.2... so that would be enough to make the difference of stable or unstable from the same twist barrel... lightbulb

 

[MontanaRifleman]

Talked with Anthony @ GS Bullets here in the states questioning him on the 30 cal 177 HV's. Told him I was planning on having a barrel made for a 300 WSM build and what would be the ideal twist for short and long range hunting applications. He mentioned that the ideal twist rate for short range vs LR terminal performance will be different. The short range requires a higher SF/twist rate which would lead to the bullet over stabalizing down range and not nosing over properly resulting in tumbling on impact.... and the ideal SF/twist rate for the LR terminal performance would result in under stabilization for short range. In the case of a 300 WSM launching the 177's @ 3300 fps the ideal LR twist would be 10 and the short range would be 9. Just something else to think about

Rich, I'm planning to finally shoot the pills you sent me probabluy at the end of next month with the GS bullets throught my RUM. I'll keep ya posted

-Mark

 

[learning]

how will you get a 300 wsm to push a 177 at 3300fps?

 

[Camshaft]

Probably with a 30"+ barrel with a very long throat to increase case capacity.

 

[jwp475]

Talked with Anthony @ GS Bullets here in the states questioning him on the 30 cal 177 HV's. Told him I was planning on having a barrel made for a 300 WSM build and what would be the ideal twist for short and long range hunting applications. He mentioned that the ideal twist rate for short range vs LR terminal performance will be different. The short range requires a higher SF/twist rate which would lead to the bullet over stabalizing down range and not nosing over properly resulting in tumbling on impact.... and the ideal SF/twist rate for the LR terminal performance would result in under stabilization for short range. In the case of a 300 WSM launching the 177's @ 3300 fps the ideal LR twist would be 10 and the short range would be 9. Just something else to think about

Rich, I'm planning to finally shoot the pills you sent me probabluy at the end of next month with the GS bullets throught my RUM. I'll keep ya posted

-Mark

I thimk that the nose not following the arc properly is incorrect. Brain Lietz has posted on here before that the only possible downside to an over stabilized bullet is added spin drift and that the bullet nose staying up is incorrect

 

[elkaholic]

Talked with Anthony @ GS Bullets here in the states questioning him on the 30 cal 177 HV's. Told him I was planning on having a barrel made for a 300 WSM build and what would be the ideal twist for short and long range hunting applications. He mentioned that the ideal twist rate for short range vs LR terminal performance will be different. The short range requires a higher SF/twist rate which would lead to the bullet over stabalizing down range and not nosing over properly resulting in tumbling on impact.... and the ideal SF/twist rate for the LR terminal performance would result in under stabilization for short range. In the case of a 300 WSM launching the 177's @ 3300 fps the ideal LR twist would be 10 and the short range would be 9. Just something else to think about

Rich, I'm planning to finally shoot the pills you sent me probabluy at the end of next month with the GS bullets throught my RUM. I'll keep ya posted

-Mark

Hey Mark! I thought you transferred to Mars or something. Good to hear from you. I don't remember exactly which bullet I sent you but if it's what I think, I probably have a better one currently. Keep me posted.....Rich

 

[MontanaRifleman]

I thimk that the nose not following the arc properly is incorrect. Brain Lietz has posted on here before that the only possible downside to an over stabilized bullet is added spin drift and that the bullet nose staying up is incorrect

Interesting JW... I'll ask Anthony next time I talk to him to see why they are thinking that. I know they have done extensive testing with their bullets and he did say that guys were actually doing this intentionally with thier very high BC SP (Speer Point) bullets that are solid non-expanding bullets, so they tumble on impact at long range to do damage.

Hey Mark! I thought you transferred to Mars or something. Good to hear from you. I don't remember exactly which bullet I sent you but if it's what I think, I probably have a better one currently. Keep me posted.....Rich

Rich, they were the brass tipped 210's, very nice looking pills I didn't want to try anything longer with my 10 twist. I'm stoked to get them down range.

 

[MontanaRifleman]

how will you get a 300 wsm to push a 177 at 3300fps?

Here we go....

Abara Cadabara... Hokus Pokus... JK

I'm close to 3200 fps (about 3190 or so) with RL17 and 180 E-Tips in my SAKO with 24 3/8" barrel. This is 200 fps faster than I get with the E-Tips,or other 180 bullets with other powders. I've gotten the same 200 fps boost in velocoity in my 25-06 and RL17. GS bullets, because of their design and moly coating will get anywhere from 50 fps to 200 fps greater velocity than other bullets of same weight. I'm expecting about 100 fps more with the GS bullets because of their design. I'm also going with a 26" bbl (1 5/8" longer) wich should buy me another few fps. Then there's the Gun Juice treatment (or maybe nitride).

This is of course is speculation, so I'll see what happens when it hppens which probably wont be for another year or so because of custom barrel lead times, and gun smith schedules, etc.

Cheers,

Mark