90 gr Federal TNT disassembly, 6.5G

[grayfox]

I'm working up some 90 gr loads for my new 18" Grendel.
I took one of the Federal-90's apart to look at it.
The TNT bullet they are using has a cannelure whereas the TNTs in my box of 100, do not. Otherwise overall length, look and shape they are the same when laid side by side.
The powder measured 29.7 gr, looks kind of like H335 or maybe CFE, the silvery/dark flat pellet-like appearance. (I put the round back together before taking any pix, sorry.) I'm pretty sure it's not either of them... the advertised velocity is 3000 f/s - probably 24" barrel, but I don't have any 29.7-ish powders that could do that...
COAL for 3 measured 2.183, 2.178, 2.182, with a slight crimp into the cannelure.
Anyway, just a little info on them.

My loads are going to be H335, Hornady new brass with cci450, loaded 2.180 so they will be similar in length to the Feddies. 30.6, 30.8, 31.0, 31.2, 31.4, 31.6 gr.
My OBT estimation routine can't find one in the book-powder ranges any higher than ~2790 (24") or est. 2700 for 18" barrel. So I'll see what results come out of the shooting...
If I find a good grouping then I'll chrono it after some validation.

I'm trying to find a 90 gr combo that comes close to the Federal one or else one that shoots well out of this barrel for predator hunting, the Fed-90 gives me ~0.8-1.0" at 100 yds so far, at ~$0.97/round. This barrel is the 18" grendel hunter, 1-8/5R SS barrel I got recently (bought it as an upper assembly).

[BluntForceTrauma]

Very interested in this project. Good luck!

I think you're on the right track with H335.

[VASCAR2]

Another good powder with the 90 grain TNT HP is A2230/Xterminator, has worked well for me.

[grayfox]

I didn't see any 2230 data in either vol 2 of the grendel book or in Western powders, they have data for the 85 Sierra tho. I wouldn't be opposed to it however...

[grayfox]

The rig, and some of the components...
well, soon. Gotta work on the pixel sizes...

[grayfox]

Results from today - 100 yd

Results.
The Federal AE/90 set is in the center, and 30.6-31.0 on pix #1. Pix #2 has the 31.2-31.6.

[Clays23]

Nice, looks like 31.2 is the sweet spot

[BluntForceTrauma]

Chrono!

[grayfox]

Roger that to both! Will re-validate a couple more times then on to speed testing.

[grayfox]

Range day

OK, today was range day. I have my 90 gr TNT90 handloads and some Federal TNT-90s available and my magnetospeed.
Also one set of 123SST factory loads.
This is for my 65 Grendel Hunter upper.

This is a 100 yd, indoor range. Temp was a bit warm probably 75 deg F.

90 gr TNT Handloads, Hdy new brass, H335 at 31.2 gr, cci 450, 2.180 COAL

1 - 2770
2 - 2653
3 - 2765
4 - 2774
Avg 2765, SD 9

90 gr Federal 90 TNT factory

1 - 2890
2 - 2876
3 - 2895
4 - 2895
Avg 2889, SD 8

123 sst, factory (box says 2590)

1 - 2525
2 - 2520
3 - 2501
4 - 2506 Avg 2513, SD 11.

After chrono I shot a couple of groups of the handloads.
1 called flyer in the second group.

Group 1: 0.531 ctc
Group 2: 0.338 ctc

The H335/ 31.2 handloads may not have the exact same POI as the Federals but from earlier shooting they are pretty close, within 1" of each other, maybe closer (could be that the diff is the shooter), even with the Feds being ~125 ft/sec faster.

I attached a pic of the 2 groups.

[Kilco]

Holy moly those fedral loads are smokin!

[BluntForceTrauma]

That's what I'm thinkin! Somebody finally did their homework!

[LRRPF52]

Pretty sure they use a canister powder engineered for them.

Your 90gr Federal factory loads pretty much mimic mine from Lilja 318. (started out 18.25", cut down to 17.6")


90gr TNT clocks an average of just under 2900fps from my 17.6" Grendel.

One string of 5 averaged 2900.4fps, the other 2880.8fps. It's fast and accurate.

[sneaky one]

G fox, Federal can cut grooves , and do the cannelure on site - as per requested. And cut the tails on the base... I had a few barnes cut with 6 grooves- there-- to a no gain a while back.

It's hi speed small item CNC on site. Many of them.


Some of the blem bullets from the past have a cannelure, when it wasn't requested, they shoot awesome, btw... buy them online at different sites;

Powder specs are a closely held secret. At Feddy.

Yet through handloading- you can closely mimic towards the upper speeds. It/s not that hard to do. I've done all the groundwork on my own,

PM me if a question pops up.


Awesome to see the --- finally -- some excitement on the lighter pills. JAS and Bill A ., enlightened me years ago of this 6.5 round. Think less than 110 grns.

All my work on monos was 105 gr. & less. GRRRRRRRRRR rocks....

It's the best AR hunting machine out there. As far as caliber, function, accuracy,,, lethality , Reach, etc. In a low recoil unit.

Penetration is beyond my expectations. WOW!

[grayfox]

G fox, Federal can cut grooves , and do the cannelure on site - as per requested. And cut the tails on the base... I had a few barnes cut with 6 grooves- there-- to a no gain a while back.

It's hi speed small item CNC on site. Many of them.

Some of the blem bullets from the past have a cannelure, when it wasn't requested, they shoot awesome, btw... buy them online at different sites;

Powder specs are a closely held secret. At Feddy.

Yet through handloading- you can closely mimic towards the upper speeds. It/s not that hard to do. I've done all the groundwork on my own,

PM me if a question pops up.


Awesome to see the --- finally -- some excitement on the lighter pills. JAS and Bill A ., enlightened me years ago of this 6.5 round. Think less than 110 grns.

All my work on monos was 105 gr. & less. GRRRRRRRRRR rocks....

It's the best AR hunting machine out there. As far as caliber, function, accuracy,,, lethality , Reach, etc. In a low recoil unit.

Penetration is beyond my expectations. WOW!

Thanks sneaky, I might just do that. For now though I'll stick with the 31.2 H335, it's shooting very nicely out of my GHtr.