A new 77gr in town

[grizzman]

I’ve been curious how the RMR 75s have been flying. I haven’t loaded any of them yet.

[MarshallDodge]

Nosler 77 grain CC G7 BC .193
Lapua 77 grain Scenar G7 BC .203
Sierra 77 grain SMK G7 BC .190
Sierra 77 grain TMK G7 BC .210
Berger 75 grain VLD G7 BC .217
Berger 80 grain VLD G7 BC .228


And then we have:

MEAD 5.56 X45 77GR BTHP G7 BC .243 ??

Nope, sorry not buying that BC #. Fib about one thing, sort of tarnishes all things. I'm going to wait this one out, and let someone else be the beta tester.

Hornady 75 ELD is .235 G7

Listed BCs are typically average. Out of a 22 Creedmoor at 3277, that may be the BC they are seeing.

[markm]

I’ve been curious how the RMR 75s have been flying. I haven’t loaded any of them yet.

75 gr has always been harder to get to shoot great than 77 gr for me. I get lazy about working up a load anymore.

[1168]

Hornady 75 ELD is .235 G7

Listed BCs are typically average. Out of a 22 Creedmoor at 3277, that may be the BC they are seeing.

Sierra lists multiple BCs based on velocity. I’ll have to take a look at some of the bullets being compared.

75 gr has always been harder to get to shoot great than 77 gr for me. I get lazy about working up a load anymore.

Its the secant ogive on the Hornadys, not the bullet weight. Are the RMR 75s secant, or tangent?

[markm]

Sierra lists multiple BCs based on velocity. I’ll have to take a look at some of the bullets being compared.

Its the secant ogive on the Hornadys, not the bullet weight. Are the RMR 75s secant, or tangent?

RMRs are just like SMKs... tangent.

[1168]

RMRs are just like SMKs... tangent.

Might be easier to work up than Hornadys, then.

On the original topic, I just looked at some BCs. .243 G7 is better than anything less than 90gr, and this one is untipped. Color me pessimistic. Reminds me of the gun company that decided they were going to make silencers and blabbed all over the internet about 109dB with supersonic 5.56. Sometimes newcomers don’t know how to measure properly and think they’ve achieved “nevah bin dun befoe” on their first whack.

[MarshallDodge]

Might be easier to work up than Hornadys, then.

On the original topic, I just looked at some BCs. .243 G7 is better than anything less than 90gr, and this one is untipped. Color me pessimistic. Reminds me of the gun company that decided they were going to make silencers and blabbed all over the internet about 109dB with supersonic 5.56. Sometimes newcomers don’t know how to measure properly and think they’ve achieved “nevah bin dun befoe” on their first whack.

Again, BC is based on several factors, including velocity. They could be posting the max value rather than the average of several velocities. I've shot the 75 Amax out of my 223AI at 3050 FPS and found the BC to be better than what was on the box. That added 150 FPS really makes a difference compared to a standard 223 load.

The BC value is printed to get you close, just like the velocity on a box of ammo.

Comparing them between manufacturers is similar to the horsepower game that auto manufacturers play.

[vicious_cb]

I get it they are using the max BC from some hot rodded Creedmore load, while technically correct its still disingenuous. Better to post the numbers from .223/5.56 loads out of reasonable barrel lengths because I doubt many people are going to be loading these in a 22 Creed.