120 class powders

[Dt219]

[DIANEB]

Benchmark and A2520 work great with the 120 ELD's in both my Grendel's...

[Dt219]

I do have benchmark. I did assume it was a fuzz to fast for the 120s Getting any velocity ?

[mdram]

xbr and arcomp both give me 2450 from a 20" with 123gr

[grayfox]

+1 on the ar comp and xbr.
with 3# of the xbr I would use that.
Just work up be watchful. You should get 2450, maybe up to 2475 look for the node.

[mdram]

+1 on the ar comp and xbr.
with 3# of the xbr I would use that.
Just work up be watchful. You should get 2450, maybe up to 2475 look for the node.

just check, at max i was over 2500, but 2450 range was my best groupings

[outbreaker]

My first choices are

1. Benchmark (if you can find it) due to temp stability and accuracy
2. TAC Just as accurate as benchmark with a little less temp stability

[EastTNHunter]

[Klem]

Dt,

AR-Comp will give the most velocity and with 100% powder burnt out of those three powders at max peak pressure, with a 120 or heavier bullet, in a 20" barrel. H4895 will be close behind it but slightly lesser velocity because it is a single-based powder (Comp is double-based). In third place is the fastest burning powder, XBR which will max out at the slowest velocity.

All will give the velocity you are looking for before reaching peak pressure or full case.

XBR and 4198 are single-based powders so should be more temp stable than Comp, but that's only the theory and might not be the case when you use them.

Your barrel might prefer something other than the theoretical best.

[dexdog]

In addition to ARComp, Benchmark and 8208xbr, I have had good groups with VV N530 using a 120 SMK in my Howa 1500 mini HB. The Vhthavouri reloading page says starting load of 22.7 gr for the 123gr Lapua Scenar, with a max of 25.0gr. I have done some testing in my Howa 1500 mini HB and settled on 23.5 gr N530 as most accurate. The 23.5gr gave me a velocity of 2360 using a Labradar at about 80 F, elevation 400 feet MSL. I also use Benchmark, but have had best results with lighter bullets in the 85 to 107 grain range

[Dt219]

[Klem]

Dt,

What does 1.625 refer to? COAL should be about 2.3" for this calibre (base-to-tip length).

If 1.625 is using the Hornady B350 insert then be aware those inserts are mass produced and your internal diameter will likely be slightly different to everyone else's. It makes it risky comparing metrics on the Forum this way.

[grayfox]

A 120, like that eldm, is a tangent ogive, more "stubby" so can't load it as long as say a 123 bullet, Eldm or sst.

[LRRPF52]

[myrifle]

Yes the speed is up because the powder is compressed.

With the powder compressed, you dont have any room too change seating depth, so you will have too leave the load as is.

If you move towards the lands. One of two things will happen. You will either lose a few fps and the group will open or possible close but more then likely your going to spike the pressure.