243 Win. IMR 4451. Sierra 85 gr hpbt #1530 data.

[243winxb]

Please post your results, if using IMR 4451 in the 243 Win. Ty.

Not much data that i could find. So here is mine. Sorry no velocity.

IMR 4451 IN 243 Winchester. Sierra 85gr hpbt #1530.

Rifle- Remington 600 Mohawk. 18" bbl.

Rem brass, Redding fl bushing die, no expander. .270" bushing.

CCI Br2 primer . Flash hole uniformed. Temperature 40 degrees. No wind.

100 yards IMR 4451 -44.0 GR 5 shots = .905" The first shot from clean barrel opened group. Just measuring the 4 =.482"

IMR 4451 - 44.5grs = 5 shots -.733"

Col 2.640" Sizing only 1/2 of the necks with the bushing.

Fired 1 round of each at 45.0 & 45.5grs to look for pressure. Seen no pressure signs.

I don't see any less copper fouling with this powder? Very old factory barrel. Many rounds fired.

I worked up from 37.5grs. because of Hodgdons 90gr bullet data for safety. It was a long road , working up.
I suggest working up using the Hodgdons/Sierra 80 gr data. Do so at your own risk. Be safe.

 

[horsey300]

Please post your results, if using IMR 4451 in the 243 Win. Ty.

Not much data that i could find. So here is mine. Sorry no velocity.

IMR 4451 IN 243 Winchester. Sierra 85gr hpbt #1530.

Rifle- Remington 600 Mohawk. 18" bbl.

Rem brass, Redding fl bushing die, no expander. .270" bushing.

CCI Br2 primer . Flash hole uniformed. Temperature 40 degrees. No wind.

100 yards IMR 4451 -44.0 GR 5 shots = .905" The first shot from clean barrel opened group. Just measuring the 4 =.482"

IMR 4451 - 44.5grs = 5 shots -.733"

Col 2.640" Sizing only 1/2 of the necks with the bushing.

Fired 1 round of each at 45.0 & 45.5grs to look for pressure. Seen no pressure signs.

I don't see any less copper fouling with this powder? Very old factory barrel. Many rounds fired.

I worked up from 37.5grs. because of Hodgdons 90gr bullet data for safety. It was a long road , working up.
I suggest working up using the Hodgdons/Sierra 80 gr data. Do so at your own risk. Be safe.

View attachment 887609

Hodgdon has 85 gr ttsx data for the i4451 I used that as my jumping off point. 40.7-43.8. with it being a copper I can go a little higher with Speer Sierra Hornady 85 class but in general, my uses reflect your findings!

 

[243winxb]

Hodgdon has 85 gr ttsx data for the i4451

The all Copper & GMX type bullets seem to be of very different construction, when compared to the Sierrs 85 gr hpbt.#1530.

I just remembered, Sierra data lumps 3 bullets together & uses generic powder charges.

Hodgdon lists the 80 gr btsp. Working up with IMR 4451 & Sierra 80 gr data should be safe.

Old photo of generic data.

 

[stillquietvoice]

My old Speer manuals did the same each company uses their own products and know their construction so the data will work with any of them. It was easier to lump data for several bullets than to do exclusive development for each bullet and it took less space in the book.

 

[243winxb]

The copper fouling eliminator in IMR 4451 doesn't seem to reduce copper, when compared to IMR 4350.

In fact 4451 seems to make more copper. Its a double base powder containing Nitroglycerin , where IMR 4350 is single base.
The Nitroglycerin powder may burn hotter, leaving more copper deposits?
I will be going back to 4350 when the 2 lbs of 4451 are used up.

Sds for 4451 types.