270Weatherby
Well-Known Member
- Joined
- Aug 17, 2009
- Messages
- 124
Anybody have a starting point for RL 17
120gr Barnes TTSX
.284 Win
I see 180gr Bergers maxed at 53gr
120gr Barnes TTSX
.284 Win
I see 180gr Bergers maxed at 53gr
Anybody have a starting point for RL 17
120gr Barnes TTSX
.284 Win
I see 180gr Bergers maxed at 53gr
Fitch,
Could you do us a favor and run 67.5 gr of RL17 in a 300 WSM (24 3/8" barrel) with 180 E-Tips and 55.5 gr of RL17 in a 25-06 (26' barrel) with 115 Ballisitc Silvertips? I am very curious to see what the program says vs what my chrony is telling me.
Thanks,
Mark
Thanks for the help Fitch. I'll start at 48 or 49 and work up until I see pressure and back off 10% or 1/2gr.
Fitch,
According to Nosler, the 180 E-Tip's length is 1.464"...
Nosler - Bullets, Ammunition, Rifles, Brass, and Reloading Data.
My measurement is 1.475". I don't have any 180 AB's (1.38") or BT's (1.36") to compare it with, but Nosler lists a slightly higher BC for the E-Tip (.523) vs the AB and BT (.507) I'm sure the bearing surface of the E-Tips is longer, as the bullet itself is longer by about .1"
The Ballistic Silvertip has a lubalox coating which is an oxide, not a moly. I had a chat with a Nosler tech on the subject and he told me it was quite different. It's meant to reduce fouling which I haven't really seen any evidence of. It (like the AB) is basically the same as BT in design and structure.
Your velocites are close to what I'm getting but hopefully your pressures are not. With the E-Tips, I'm getting 3193 from one chrony and about 30 fps less with the other (slower) chrony. In looking at all the evidence, the faster chrony appears to be more correct. My COAL was 2.93" (subtract .1" to use the AB in it's place for case capacity). Brass was neck sized only and therefore slightly swollen. Primers were somewhat flattened but not crater and bolt lift was easy, slighty stiff at 1/2 gr higher charge.
The velocity for the 115 BST's was about 3405 (with the slow chrony) and Win brass. Recently I treid the same load in Rem brass and got about 30 fps more velocity. Pressure signs similar as those reported for the 180 E-Tips.
Just to humor me, could you run the 300 WSM data for the E-Tips and 65.5 gr of H4350?
Thanks,
Mark