H335 and TAC, which to start with?

[redhat]

I have both on hand (and will eventually try both) looking for a starting point.

I have a bit of Starline primed with CCI 450, and 123 grain Match Monsters going through a 16" Ballistic Advantage barrel. I have enough of these powders that sourcing an additional (e.g. 8208 or AR COMP) doesn't really hold interest for me, especially when supplies are scarce.

Option A: TAC 25.4, 25.7, 26.0, 26.2, 26.5, 26.7, 27.0, 27.5, 27.5, 27.8, 28.0, 28.2 (Using Western's starting load for 123 grain Sierra HPBT*, moving up in 1% increments - there are some roundoffs between the .2 and .3 increase per step in the ladder) Western, Nosler, and Hornady all start at 25.4-25.5 and move up from there with different max pressures; as Western's max of 28.2 is noted to exceed the 50k psi mark, I may roll this back to the 27.5 that Nosler lists as a max.

Option B: H335 25.6, 25.8, 26.1, 26.4, 26.6, 26.9, 27.2, 27.4, 27.7, 28.0, 28.3, 28.5, 28.7 (consulted Hornady and Hodgdon - Hornady gave a low end of 25.6, so that's where I started - Hornady cut off at 27.3, Hodgdon kept going up to 28.7 with a chamber pressure of 49.800 psi.

* Both Western and Hodgdon data is a for a 123 Seirra HPBT, Nosler is for the Custom Competition - I'm proceeding on the assumption that these are all close enough in construction (123 grain HPBT) to the MM that the data can be used interchangeably (at least as far as approximating appropriate start/max points), even if the publishers' lawyers tell them not to certify it for anything but the tested bullet. Hornady uses GMX and A-Max, but I'm only looking to them for starting points and congruence with the other data sources.

I'm planning to fire 5 rounds at each charge weight just to see what the spread looks like and see if I can track increase/decrease in velocity variance with charge.

I also have IMR 4895 and 4064 on hand - I just don't see them come up as often in discussions on Grendel reloading.


Thoughts on which to start with?

[1Shot]

I have not tried either of the powders with 120/123s. But for what it is worth I did try just one load of IMR 4895 with Hornady 123 SSTs.
I was trying to get this bullet to shoot period. I tried it in factory ammo and many different powders and loads and neither of my rifles like this bullet period. 1 1/2 to 2 1/2 inch groups at best. I only had 5 bullets left and I loaded them up like this. Hornady previously fired case, CCI 450, 28 grs IMR 4895, 123 SST, COAL 2.250 with a medium Lee Factory Crimp applied. This was shot from my 20" BCA barrel AR. Velocity 10' from barrel average was 2416 fps, ES 19, SD 8 and 5 shot group was outside to outside .831". I wanted to try this again but was out of bullets and at the time there were none to be found. By the time they became available again I had already found loads with IMR 8208 with 120 Sierra PH and Speer Gold Dots and the rest I history. This load was real close in velocity to what Hornady factory ammo is but was MUCH MORE ACCURATE. Factory stuff shot very erratic. You might have two shots together then the next would be 2 1/2" away high right. Then the next might be 2 to 3" low left then the next be back really close to the first two. I know others have used H4895 with good results. So you will never know until you give it a try in your rifle. Good luck in your quest.

[Doorman63]

123 SMK
Starline brass
2.3 COAL (Howa Mini)
28.3 TAC
Avg 2375
SD 5
ES 12

Magnetospeed Chrono
25 degrees that day

[sundowner]

All my 123gr SST,HPBT,ELD are with H335 at 28.7 they all average 2532 in 18" barrel .

[FLshooter]

[Labrat198]

I've got the same powders and same bullets, so I am very interested in your results.

[Mustangfreek]

[LR1955]

I have both on hand (and will eventually try both) looking for a starting point.

I have a bit of Starline primed with CCI 450, and 123 grain Match Monsters going through a 16" Ballistic Advantage barrel. I have enough of these powders that sourcing an additional (e.g. 8208 or AR COMP) doesn't really hold interest for me, especially when supplies are scarce.

Option A: TAC 25.4, 25.7, 26.0, 26.2, 26.5, 26.7, 27.0, 27.5, 27.5, 27.8, 28.0, 28.2 (Using Western's starting load for 123 grain Sierra HPBT*, moving up in 1% increments - there are some roundoffs between the .2 and .3 increase per step in the ladder) Western, Nosler, and Hornady all start at 25.4-25.5 and move up from there with different max pressures; as Western's max of 28.2 is noted to exceed the 50k psi mark, I may roll this back to the 27.5 that Nosler lists as a max.

Option B: H335 25.6, 25.8, 26.1, 26.4, 26.6, 26.9, 27.2, 27.4, 27.7, 28.0, 28.3, 28.5, 28.7 (consulted Hornady and Hodgdon - Hornady gave a low end of 25.6, so that's where I started - Hornady cut off at 27.3, Hodgdon kept going up to 28.7 with a chamber pressure of 49.800 psi.

* Both Western and Hodgdon data is a for a 123 Seirra HPBT, Nosler is for the Custom Competition - I'm proceeding on the assumption that these are all close enough in construction (123 grain HPBT) to the MM that the data can be used interchangeably (at least as far as approximating appropriate start/max points), even if the publishers' lawyers tell them not to certify it for anything but the tested bullet. Hornady uses GMX and A-Max, but I'm only looking to them for starting points and congruence with the other data sources.

I'm planning to fire 5 rounds at each charge weight just to see what the spread looks like and see if I can track increase/decrease in velocity variance with charge.

I also have IMR 4895 and 4064 on hand - I just don't see them come up as often in discussions on Grendel reloading.


Thoughts on which to start with?

I have shot both and most of us did when the Grendel came out because TAC, BLC-2, H-335, 2520, and a couple others were the only powders that Alexander had tested.

First, you are wasting components and time starting at the lowest charge and working up. I do not believe I have heard of anyone here saying they started at the lowest charge and worked their way up only to find that the lowest charge was the best. They ended up using a charge in the upper end of the data. Normally within 1/2 grain of max.

I would start with 26 1/2 grains of both powders and go up by half grain increments to 28 1/2.

My bet is you will settle on 28 plus or minus 1/2 grain.

LR55

[gwtx]

I just started working on a 120 GoldDot load for my grendel 18" using H335. I used the 335 for the same reasons 'FLShooter' stated. I went from 27 to 28.3. Around 27.5 looked good, but didn't get where I wanted until I used my C-products magazine and loaded out to 2.7". Shot a 5rd group .7, and today a 3 shot .432 group. Today was primarily to chrono. The average for the 3 rds was 2464fps, SD 5 ES 10,,,I'm happy, and ready to try it on some hogs. My main powder for 120-123gr is AR-COMP, but I wanted another since arcomp has gotten scarce around here. LR55 is probably right, 27.5 to 28.5. Mine started to scatter at 28.3. Good luck

[sneaky one]

I agree with LR55-- a 7% reduction from max charge is a good start point. Accuracy seems to be best at 4-5% less than max . It's pretty easy to dial this in.

It's a small case, powder fill, burn rates, gas pressures, it affects bbl. harmonics- and speeds. Just hang out in the upper zone It'll come to you.


I've put myself to the test using lighter LFP units for 10 years here. I plowed my own road- made it work for my hunt needs.

Sorry, start with Tac. It's easy.

[lazyengineer]

In general, I'll take TAC over H335 pretty much every time in every setting.