Home Forums Hunting & Shooting Long Range Hunting 6.5 bullet ogive length questions - 123 A-max vs 140's, 142's

Can any of you 6.5 handloaders post some ogive length (tip to bearing surface) numbers for the 123gr A-max vs some of the various 140-142 gr match bullets? Or the max COL for each in your rifle would work too.

Reason I'm asking - I just picked up a 6.5 Creedmoor that needs the 123 A-max seated out to maximum mag length, or a little more, (2.855") to touch the lands. I don't have any of the heavy 6.5 bullets on hand to try out, but I'm concerned I won't be able to seat them to the lands and still fit the magazine.

Kinda disappointed, since the whole point of the 6.5 Creedmoor, vs the 260, is reaching the lands with mag length heavy match bullets.

I don't think that was the reason for the creed. It was developed to address the decreased powder charge in the 260 with long bullets at S/A mag lengths.

I had this problem with my 6.5 CM and 140 VLDs. Had to switch from BDL to a AI mag.

The amax bullets in 123 and 140 dont really need to be near the lands they shoot good with a substantial jump.
COAL of the 123 is usually around 2.71-2.75 and the 140 is 2.81.

It seems most factory 6.5 creeds will have a long jump to fit the mag. Having the bullets seated about .264 into the neck will yield an OAL that will fit the mag with most bullets. Not so with the .260 where the 140's end up cramping powder space.

I'm not worried about the 123 Amax, but the heavy VLDs and other match bullets are a different story.

I'd still like to find out how much farther out some of the 140's have to be seated to reach the lands, if anyone has that info.

That's often repeated, but doesn't make any sense if you think about it.

If the same bullet in a 260 and a 6.5C are both limited by the same mag length, then they're in the same position relative to the case head, right? The bullet base in the 260 might be back into the powder a bit, but in comparison the 6.5C has the bullet and the shoulder back into the powder space. I'm not sure why people think setting the shoulder back somehow makes up for powder capacity, when it does exactly the opposite.

Setting the shoulder back for the 6.5C moved the neck back, avoiding seating bullets in the "donut" at the neck/shoulder junction, also (ideally) bringing the throat back as well, for long match bullets to reach the lands at mag length.

Yondering,

123 Amax ogive length = .585"

142 SMK = .590"

140 Amax = .620"

That's all I have left to measure of long bullets. Won't bother giving the COAL cuz mine was a 6.5-284 LA throated to kiss the Berger 140 VLD at 3.1".

Hope it helps...

Yes, that helps, thanks! Interesting that the 142 SMK has about the same ogive length.

Based on those numbers, the closest I can seat the 140 A-max is .035-.040" off the lands.

It would be interesting the see the same numbers for the 140 VLD and 139 Scenar, if anyone has some to measure.

The creedmoor originally was specked with less freebore. There were some complaints of short brass life and pressure issues so they lengthened the freebore to .200" which is pretty long. Most reamers now are specked to .199" just barely off the factory specked chambers.

It's not so much the weight of the bullet as it is the steepness of the ogive. I'll bet you could kiss mag length with a nosler 140 cc for example but not a Berger vld.



Bb

A few measurements, plus or minus...

140 gr Nosler Ballistic Tip: 0.852"
140 gr Hornady BTHP: 0.747"

To the lands, Ruger M77 Hawkeye Predator
140 gr NBT: BTO 2.252" COAL: 2.775"
140 gr H BTSP: BTO 2.260" COAL: 2.837"
123 gr H A-Max: BTO 2.238" COAL: 2.812"

Thanks. These must be base to ogive measurements? Tip to ogive is what I needed, but your COL numbers work for that, thanks.

Good timing on this thread.

120 TTSX?
127 LRX?
129 ABLR?
130 Berger Hunting?

These four look like .7 ish nose length to my old eyes.

The tip to ogive length on the
120 TTSX is .543
127 lrx is .593,
130 HVLD is .669 average (from .665 to .673)
140 HVLD is .665 average (from .663 to .667)

If I could find a 129 ABLR I would measure it for you but I have never even seen one in person. Hoping to try them as soon as I can get a box.

This was using the Hornady gauge.

Great info, thanks!

Yeah I'll say.

Thanks 8nbait and MojoHand