How fast are you pushing 140 ELD-Ms?

Killbillc68 said:
I don’t have my reloading book handy but I also have a 6.5 Creedmoor CTR Tikka 143 eld-x h4350 Just shy of 2600 FPS with good accuracy and ES. In my rifle if I push them any faster I hit pressure. Does anyone have any theories why these rifle seem to be a bit slower than normal?
Click to expand...

Is your CTR a 20" or 24" bbl? If it's 20" I'd say that's the reason you're having trouble getting more speed.

I went with 130gr Bergers from my 20" CTR in 260 Rem to get some more speed from the short tube.
 
Lead hammer said:
Do you have any brass that you could measure the length on that were used at a lower charge to compare? You may find a charge weight where the cases grow fast. Or you might find the velocity oddly spikes up someplace on your test charges.
I run Hornady brass, H4350 and at 41.5 i run into pressure with 143ELDx.
Same brass, same powder, but at 41.1, and 140 VLD hunters, I have zero pressure problems but the are the same velocity as the ELDx.
2710fps.
24" Savage barrel.
I have a great node up at 42-42.3 with the Hornady's but its just too much for my rifle.
My VLD hunter load has room for more FPS (according to lack of pressure signs ) but it shoots too good to mess with, and my brass is happy as well. 0.003" stretch.
Most of the online loads I see that run hotter, with any powder, have good brass and usually aftermarket barrels. Not sure what you are shooting.
Click to expand...

I will have to measure some of my 140 SMK brass after I fire a few and see what they are stretching.

Gun is just a savage 10 with a 1:8 twist 24" barrel
 
Alpheus said:
So a increase of 45c caused your velocity to decrease by 20fps? Yeah, physics doesn't work that way. What chronograph did you use?
Click to expand...

Labradar Doppler. Do you have any first hand results with temperature tests you could post to compare?
 
H4350 is the powder for 6.5 Creed, may not have the velocity but it has the consistency and repeatability.

Alpha SRP, 140 RDF, 41.5g H4350, 10 round strings various temps through the year not sure of exact temps, 8 firings on brass trimmed once after first firing and after 4th, no substantial growth since.

200 rounds on barrel - 2753 Fps, SD 6 ES 20 winter (.6" group)
600 rounds on barrel - 2752 Fps, SD 5 ES 20 spring
1800 rounds on barrel- 2749 Fps, SD 3 ES 10 summer (.57" group)
 
Camoman1 said:
H4350 is the powder for 6.5 Creed, may not have the velocity but it has the consistency and repeatability.

Alpha SRP, 140 RDF, 41.5g H4350, 10 round strings various temps through the year not sure of exact temps, 8 firings on brass trimmed once after first firing and after 4th, no substantial growth since.

200 rounds on barrel - 2753 Fps, SD 6 ES 20 winter (.6" group)
600 rounds on barrel - 2752 Fps, SD 5 ES 20 spring
1800 rounds on barrel- 2749 Fps, SD 3 ES 10 summer (.57" group)
Click to expand...

That is impressive consistency across all seasons.
 
todbartell said:
Labradar Doppler. Do you have any first hand results with temperature tests you could post to compare?
Click to expand...

Myself? Nope, but Applied Ballistics, Hodgdon's and PrecisionRifleBlog, among others, are pretty solid references in my book. How about this: https://apps.dtic.mil/dtic/tr/fulltext/u2/a425264.pdf Page 5 has a nice chart. That pdf also mentions the additives that can be used to reduce temp sensitivity, lead or copper salts and something called carbon black. Also, the US Army developed a new round, the Mk 316 Mod 0, because the M118 that used RL15 was experiencing pressure spikes in hot desert climates.

If you want to send me some, I'll happily give it a crack with my Magnetospeed.
 
You must log in or register to reply here.
Back
Top Bottom