The Solid Bullet Debate

[MontanaRifleman]

Just for kicks, I decided to run some hypthetical numbers comparing the 177 GS HV and the 210 Berger VLD in 30 cal. I uesd MV's of 3150 for the 210 and 3500 for the 177. These are realistic MV's out of a 300 RUM with 26" bbl. I used a BC of .631 for the 210 and BC's of .55 and .6 for the 177. I used a base Montana elevation of 3000'. Here are the results at 1200 yds...

Bullet-BC/vel/KE/momentum/windage(10 mph)

210-.631/1670/1301/50.11/76.2
177-.600/1840/1330/46.52/69.8
177-.550/1720/1163/43.39/78.6

Overall the stats are fairly close and the 177 with a BC of .6 has a definite advantage in all areas except momentum. The 210 however shows a marginal velocity for expansion, as 1800 is the "safe" recommened expanding velocity. The 177 is still well above it's expanding velocity of 1600. With a .55 BC, the 177 looses some ground but still fairly close overall and still retains more than enough expanding velocity.

At 1200 yds, the 210's effectiveness is questionable depending on weather or not it expands. The 177 is definetly a deer killer and quite possibly an elk killer with a BC of either .6 or .55.

Also, for those who prefer a controlled expansion bullet, the 177 is a one bullet solution from the muzzle, on down range.

Of course, this is a keyboard comparison. It's field performance that counts.

-MR

[Jon A]

I agree if those assumptions are correct, it will be a fine performing bullet--good enough it seems the 210 won't have much of any advantage. There are a couple big "ifs" though. The first is even the .55 comparison assumes it has a better form factor than the 210 Berger. I think the chances of this are pretty low. Next it assumes you can get an extra 100 fps or so due to its lower friction. This could very well be the case, I don't know. I ran the 173's up to 3460 with a 26.7" barrel and considered it a max load; it's possible I could have pushed them faster but I didn't try. If you need to run the 177's at 3500 to compete, even with the low friction, it's possible your brass might not last very long (especially if it's Nosler!), but like I said I don't really know.

Originally Posted by noel carlson

.30 = 9.00"

It just so happens my 300 RUM is a 1:9, so if you need me to put that to the test, let me know.

[noel carlson]

Jon,

I had not even planned on a 30 caliber when this thread began, but if your rifle is sub-minute, I may be interested in doing something within the next couple of weeks.

Do you have any objection to signing an NDA?

Best,
Noel

[Jon A]

Yup, it's easily sub-minute. I have no objections to signing an NDA.

[noel carlson]

Yesterday we learned that the ZA50/6.0-M stabilizes from a 30 caliber twist. Today we learned that it hits nothing but 10's, and X's at 1,000 yards (and this was during load refinement from a less than ideal bench set-up).

It will be competing in the 50 caliber, light rifle class, at Ratone NM on Friday, and Saturday. I hope the wind kicks up by then.

Jon, send me an e-mail at nlclsn@aol.com

Best,
Noel

[MontanaRifleman]

[QUOTE]

Originally Posted by Jon A

I agree if those assumptions are correct, it will be a fine performing bullet--good enough it seems the 210 won't have much of any advantage. There are a couple big "ifs" though. The first is even the .55 comparison assumes it has a better form factor than the 210 Berger. I think the chances of this are pretty low. Next it assumes you can get an extra 100 fps or so due to its lower friction. This could very well be the case, I don't know. I ran the 173's up to 3460 with a 26.7" barrel and considered it a max load; it's possible I could have pushed them faster but I didn't try. If you need to run the 177's at 3500 to compete, even with the low friction, it's possible your brass might not last very long (especially if it's Nosler!), but like I said I don't really know.

I bekieve the form factors of the two bullets are probably very close with edge going to the Berger because of a smaller meplat. But I'm *guessing" that the meplat of the 177 isn't a whole lot bigger. Why would you say that the 177 couldn't have a BC of .55 unless it had a better form factor? Do you think 33 gr of mass will make that much difference... .081 in BC? I'm thinking if the E-Tip BC really is .523, the 177 should be at least .55 if not more. Aslo, the greater velocity of the 177 (~ 3500 fps) will/should boost it's BC performance. I suppose 3500 fps is an "if", but I think it's doable without over pressure. On your experience with the 173... did you see any pressure signs beyond 3460, or did you just stop, and what powders did you try with it?

Too bad that I'll probably have to wait fro 3 months to shoot these things

[MontanaRifleman]

Noel,

Congrats again today.

Glad to see Jon stepping up to test some 30 cal bullets. If I had a 9 twist, I would step up also. Please keep us posted on progress

-MR