QuintusO said:

When I said they didn't know, I meant specifically during the development of the .30 M1906. Anytime after 1925? Yes, they knew, and it's extremely frustrating that they didn't seem to care.

You're right for the Mle1906, and I extended the discussion too fast.

I agree that reducing the ogive height from 25 mm down to 23 mm in 1906, while a move in the wrong direction, can't be regarded as a bad decision at this time.

Further reducing the ogive height from 23 mm to 20 mm for the T65 cartridge, while at the same time focusing on bullet penetration up to 1800 m, was really a bad move.

I don't think they had anything to do with it.

EmericD said:

You're right for the Mle1906, and I extended the discussion too fast.

No worries.

EmericD said:

I agree that reducing the ogive height from 25 mm down to 23 mm in 1906, while a move in the wrong direction, can't be regarded as a bad decision at this time.

Not sure I understand. Ogive space got longer with .30-06, not shorter.



 

EmericD said:

Further reducing the ogive height from 23 mm to 20 mm for the T65 cartridge, while at the same time focusing on bullet penetration up to 1800 m, was really a bad move.

I understand why they did that, what I don't understand is why they seemingly made no effort to produce a streamlined bullet within that format. Even more bizarrely, the British made exactly the same mistake, and the 140gr Type C bullets for the .280 are no more aerodynamic than their .30 cal counterparts.

The only excuse - and it is a thin one - that I can think of is that during this time the science of supersonic aerodynamics was only just maturing, so maybe there wasn't enough institutional motivation? Certainly a large brain drain occurred in the Army after WWII, as those people left to go to the Air Force and private sector.

Sending this because I don't really trust private messages on delphi (they seem to get eaten a lot). I imagine you only check emails at your work address during the week, but I sent you some things yesterday I think you would find very interesting. I don't know if you can check it, or shoot me some other address I can forward them to.

QuintusO said:

Sending this because I don't really trust private messages on delphi (they seem to get eaten a lot). I imagine you only check emails at your work address during the week, but I sent you some things yesterday I think you would find very interesting. I don't know if you can check it, or shoot me some other address I can forward them to.

use the same address but with "@def.gouv.fr" for the domain.

Thank you. Sent.

Some more info about TV ammo posted on TFB.
 

One of the many, many things that has sucked about this pandemic is that it seriously delayed the commercial launch of TV's cases in partnership with Sierra. 

Pre-Covid, they were due to be released right about now. 

QuintusO said:

it really confuses the heck out of me why the projectile shape for .276 Pedersen wasn't inherited by the .30 T65 program. I honestly have no answer to this, they simply went back to the M1906 shape in 1944 for seemingly no reason and then they kind of half-assed a secant ogive in there last minute.

Might it have something to do with the limited size of safety zones at practice ranges?

As I recall, the .30-06 M1 Ball round, which had a 170 grain boat-tailed bullet, was replaced by the M2 Ball (150 grain flat-based) for two reasons: the M1 didn't work too well in the Garand, and "complaints were being received from the field about the longer range and greater danger space caused by the M1 Ball Cartridge" (quote from HWS).

So the M2 Ball was developed, which ironically was almost identical to the Model 1906 Ball cartridge (the original loading). Maybe the Army didn't want a very long range.

autogun said:

Might it have something to do with the limited size of safety zones at practice ranges?

I doubt that, honestly. The maximum range of 7.62 M59 is 1,000 yards further than .30-06 M2 Ball. If they'd wanted to limit maximum range, they would have stuck with the 140gr T104 Ball, which had a slightly shorter maximum range than M2 Ball.

autogun said:

As I recall, the .30-06 M1 Ball round, which had a 170 grain boat-tailed bullet, was replaced by the M2 Ball (150 grain flat-based) for two reasons: the M1 didn't work too well in the Garand, and "complaints were being received from the field about the longer range and greater danger space caused by the M1 Ball Cartridge" (quote from HWS).

175gr M1 Ball is the round the M1 was designed for. Where are you hearing it didn't work well in it?

 

autogun said:

So the M2 Ball was developed, which ironically was almost identical to the Model 1906 Ball cartridge (the original loading). Maybe the Army didn't want a very long range.

Then, again, why switch from 140gr FA T11 (T104) to 150gr FA T21 (T104E2)? Why switch from the tangent to secant ogive?