6XC load data for 80 GN sierra Varminters

[urbanrifleman]

What is your Freebore?

 

[59f100292]

Unknown. I purchased the gun used, and seller didn’t have specifics on the reamer, or even who did the work as he purchased it used also. I can provide cartridge base to ogive measurements to the lands when I have them in front of me if that’s of any value to you.

Any one know who marked their barrels with MTG? Supposedly some tikka specialist from California?

 

[KMart]

MT Guns?? Santa Barbara Ca. Closed their shop in 2015

Any one know who marked their barrels with MTG? Supposedly some tikka specialist from California?

 

[59f100292]

MT Guns?? Santa Barbara Ca. Closed their shop in 2015

Maybe. I’m not near the rifle but my memory is the barrel is stamped MTG followed by a 6 or 7 digit number, almost like a serial number.

 

[59f100292]

For heat index you can look at this barrel life calculator and when you select a powder it will show you the heat index.
https://pierrevanderwalt.com/barrel-life-calculator/

The lower the index the longer barrel life will be. AA-2700 has a heat index of 3545.
Hybrid100V also has a low heat index of 3545.

H-380 has a heat load index of 3970 and according to Quickload ( I adjusted QL burn rate factor to your chronograph verified velocity and guessed outside temp around 85 f ) Near Maximum load of H-380 ( at 59,000 psi) is around 40.7 gr, and velocity from your 28" bbl estimated at 3,500 fps.
I you're happy with the accuracy of your 39.2 gr load, I would stick with it because as pressure raises, barrel life shortens.

Very interesting website. Just spent some time fooling around with it. I’m not sure how relevant it is without knowing the pressure of your load. With out it, it looks like it assumes everything is 55,000 psi. I suspect to get the most from it someone would need something like quick load to get their pressures. Any thoughts?

 

[Zero333]

Very interesting website. Just spent some time fooling around with it. I’m not sure how relevant it is without knowing the pressure of your load. With out it, it looks like it assumes everything is 55,000 psi. I suspect to get the most from it someone would need something like quick load to get their pressures. Any thoughts?

Quickload would be the easiest tool for estimating pressure, and when someone knows how to true to inputs in Quickload it should suffice. But even quickload may be off by as much as 5,000 psi even with good inputs.
There is rifle pressure testing equipment available for like $ 600 or $ 700. I think it's called "Pressure Trace"

You're always welcome to Message me anytime you want Quickload data.

 

[59f100292]

Quickload would be the easiest tool for estimating pressure, and when someone knows how to true to inputs in Quickload it should suffice. But even quickload may be off by as much as 5,000 psi even with good inputs.
There is rifle pressure testing equipment available for like $ 600 or $ 700. I think it's called "Pressure Trace"

You're always welcome to Message me anytime you want Quickload data.

Thanks for the offer.

 

[Spike A]

From the new Sierra Edition VI Manual
View attachment 1114853

I know this is an older thread but I can’t get this image bigger to read... any way of getting it? I just picked up some of the 80’s for chuck hunting ...
Thank you

 

[Idaho-Lefty]

I use, the STARTING Loads of, the 6mm CREEDMOOR Data from, the Hogdon Reloading site and work up carefully, from there. The Creedmoor uses about, 2.5 to 3 grains more powder than the 6XC.
Am currently loading / Testing, the 80 gr. Varminter's with, 40.5, 41.0 and 41.5 grains of IMR 4350 in my 6XC.
Looks like, around 42.0 grs of, IT, is "probably",.. MAX. for the 6XC ! The lower charge of, 40.5 grs was, sub 1/2 MOA.
In my .243 Win Tikka, this Bullet, ( same Powder, just more of it ) LIKED to "Jump" about .040 / .045 !
Hope this, helps !

 

[Spike A]

I use, the STARTING Loads of, the 6mm CREEDMOOR Data from, the Hogdon Reloading site and work up carefully, from there. The Creedmoor uses about, 2.5 to 3 grains more powder than the 6XC.
Am currently loading / Testing, the 80 gr. Varminter's with, 40.5, 41.0 and 41.5 grains of IMR 4350 in my 6XC.
Looks like, around 42.0 grs of, IT, is "probably",.. MAX. for the 6XC ! The lower charge of, 40.5 grs was, sub 1/2 MOA.
In my .243 Win Tikka, this Bullet, ( same Powder, just more of it ) LIKED to "Jump" about .040 / .045 !
Hope this, helps !

right, that was/is my plan ... but then saw this and thought just maybe... I have the 5th edition ... I’m planning on using h4350...

 

[Hpwrshooter]

What twist barrel are you shooting. I tried 80gr Berger varmint bullets with 38gr of H4350 in a 7.5 twist and was blowing up bullets. Seems the jackets on the varmint bullets were too thin for that twist

 

[6MMsteve]

I'm running 40grs of re23 in my 6xc with 85 smk's

 

[Idaho-Lefty]

I'm testing, 40 to 42 grains of IMR 4350, in 1/2 grain increments with, the 80 gr. Sierra Varminter's in my 6 XC
I like, either of the 2, 4895's with, the 70 or, 75 grain Bullets.
But at, 80 grain plus, weight bullets, I switch to, the 4350 Burn rate powders, for my .243 and 6 XC loads.
Testing, is going SLOW right now,.. due to Windy conditions !

 

[Spike A]

What twist barrel are you shooting. I tried 80gr Berger varmint bullets with 38gr of H4350 in a 7.5 twist and was blowing up bullets. Seems the jackets on the varmint bullets were too thin for that twist

Sierra designed these bullets for the 243 class cartridges for varmint hunting

 

[Idaho-Lefty]

YAHOO !!!
41.3 grains of, IMR 4350 with, the #1515 Sierra Varminter's, in my 1-7.5 TW, 6XC is grouping SUB 1/2 MOA Cloverleaf's ! Goodbye to, the inconsistent, grouping,.. 87 V-Maxes !
Haven't Chrono'd this load, yet, but they are "nasty", on Sage Rats !
The 95 gr Classic Hunter load, was just OK with, 41 gr's of, StaBall ( Bullet cut them, in Half ) BUT, I don't need, the extra Recoil or, Expense for, 100-300 yard shots, on Whistle Pigs.

 

[Idaho-Lefty]

I will be comparing, the 80 grain Berger Varmint HP's with, the #1515 Sierra's,.. next.
For accuracy @ 100- 300 Yards, acrobatic's and "Shred" Factors,.. on Sage Rats.
IMR 4350 works, great ! But will also try some, recently "scored" H-380, per 59f100's post, #18

 

[effendude]

I've settled on 40 grains of H4350 for my old 1-8" twist OTC rifles using the Berger 88 grain FB Varmint bullet. I don't know how they perform on prairie dogs but I'll find out in a couple weeks. I also loaded the 87 grain V-Max with the same charge.
Scott

 

[duke260]

6xc Proof barrel .125 freebore. This was at 160 yards. This is as far as I can shoot at my place. But this is my predator load and I really never shoot over 200 especially at night with a spotlight. I did not check the speed for the same reason, as long as it is short range and they bug hole I don’t care about the speed. The 80 grn Sierra blitz really shoots well in my br as well. Both are 8 twist.