From Heavier bullet to Lighter with Same Powder

[Flouncer]

Just checking as I have never had a bad time with my own handloads or even any overt overpresssure signs. I am reloading 8x57 using RL-17 and have easily surpassed the Hornady and Sierra load recommendations for velocity with 200g hunting bullets ..... topped out at 51.1g. Looking to extend the range using lighter and higher BC hunting bullets, I looked at the lighter Hornady 180g GMX. I figured an easy safe starting load would be to switch bullets, keep the powder weight and stay in the safe zone as I was dropping 20g of metal and had more case room and less weight. However, the Hornady manual shows a reversal of this powder trend in the 8x57 with their bullets. In several powders, the lighter 180 loads are shown topped out with less powder than the 195 bullets. ??? Erp ? ? Is this because of the GMX being a pure alloy projectile and having different friction ? As I am not using any powder listed I am somewhat at a loss. Anything to lessen the number of shots taken with a 7-lb hunting rifle is a step in the right direction. Any thoughts or recommendations regarding this powder, bullet and cartridge situation. - thanks (RL-17 is not shown in any published manufacturers data that I can find. I use it because it has shown to be faster than published loads. Also, in spite of everything 8x57 is always shown soft.)

 

[AJC]

I would call or email the powder manufacturer. They have information not published. I found this out using hunter. A wise move would be to make a short ladder starting with a listed max to be safe. Dia, bearing surface base shape all the same?

 

[Flouncer]

I messaged Alliant powder. Pretty sure I can start a grain below my 200g bullet max, say 49 or so . . .. . heh heh heh.

 

[papajoe222]

If I recall, the GMX is NOT a lead core bullet, it's a monolithic, copper alloy. The groves are for relieving pressure. I would never use load data for one bullet on one of a different weight/material
Hornady lists RL-15 Max at 46,8 gr for that bullet

 

[Flouncer]

Thanks Papa and AJC. Alliant responded electronicly in under a day and basically said they haven't tested that powder load combo and that different bullets of the same weight do not necessarily use the same quantities of powder. So I will evaluate the reduction factor in other powders with the Hornady GMX bullet data and apply that to the GMX. And, start low, as in real low.

 

[Zero333]

I personally would not use the 180 GMX because copper alloy bullets work best when they're lighter flying faster.

Consider the 160 TTSX instead. If anyone made a 140 gr alloy bullet I'd get that instead.

I have a 300winmag hunting rifle and the 130gr TTSX was phenomenal on deer compared to the 180 ttsx. And my point blank range was pretty far too.

 

[mensajd]

Lead is denser than the monolithic copper materials, hence a non-lead bullet may have a longer bearing surface than a similar mass lead core bullet (or even a more massive lead core bullet). The GMX is a lead-free bullet.

 

[2506]

If you want to go lighter in a good hunting bullet get some 180 Nosler BTs. Those 195 Hornady bullets are also really good ones. The load data for the 8x57 can be all over the place because of the old rifles with .318 bore problems. ALWAYS BACK WAAAAY OFF ON THE POWDER AND WORK BACK UP WHEN CHANGING ANYTHING IN A LOAD. Been handloading for 40 years and this is the first rule I was given by an old handloader and it is one that should never be broken. The mono bullets are a whole different critter than cup and core bullets. IMR 4064 and Varget had been really good powders for the 175 to 180 gr hunting bullets for me in the 8x57. With slow work up watching your pressure signs with the 8x57 you can pretty much equal the 30-06 with no problems. The 175 Sierra is a really great deer bullet but I have never ran it over 300 yards. Mostly under 100 yards.

 

[Flouncer]

2506 Do you consider the Nosler 180 BT an Elk Bullet ? I don't see why not except that they are advertised to expand (to ?)quickly.