270win and Barnes LRX with H4350

[Tuby27]

Did some testing in tikka t3x superlite 270win, Norma brass, cci200, h4350 worked up to 56.3gr., seated ogive at 2.765 due to mag length. best group was about .75”. Using magneto speed Chrono, it clocked in from mid to high 2900’s fps. Outside temp was about mid to high 50s. Anyone have similar velocities? Weeks prior I used a Caldwell Chrono and it showed over 3100fps. No pressure signs. Rifle has about 60rounds, never been cleaned.

 

[bdan68]

Well, according to the Barnes load data I'm looking at, 55.3 grains of H4350 is max, and they got 3,116 fps with a 24 inch barrel.

Hodgdon doesn't have data for the 129 grain LRX, but they do have data for the 130 grain TSX. They have have 55.5 grains as max for a velocity of 3,111 fps.

So it does seem as if your velocity is on the low side, since your a grain over book max. But that's really not enough to matter, and if your satisfied with the accuracy, I wouldn't change a thing.

 

[VernAK]

I've tried the very similar RL16 at 55grs under 129 LRX for 3200 area and dropped back to 54 grs at 3150 area with xceptional groups.

 

[SouthPaw]

The factory loaded barnes 129 chrono'd 3046 in my 22" 270win. I measured it just to compare to the hammer loads I worked up which finished significantly faster. Handloading the 129 with that much H4350 I'd imagine you'd be north of 3100 assuming your tikka is the standard 22".

 

[MJB]

Use a mag primer

My 270 load with TSX uses a mag primer. I stopped when I saw pressure signs back down a few grains then I backed off the lands stopped when the pattern tightens up.

 

[Tuby27]

The factory loaded barnes 129 chrono'd 3046 in my 22" 270win. I measured it just to compare to the hammer loads I worked up which finished significantly faster. Handloading the 129 with that much H4350 I'd imagine you'd be north of 3100 assuming your tikka is the standard 22".

Yes factory 22” barrel. I was hoping the velocity was up in the 3100 range just like it was when I used my Caldwell Chrono, can’t use it now since the negative battery wire broke off, will weld it back and see if it works. But I used my buddies magneto speed and it stated mid to high 2900’s. Not sure which one is more accurate.

 

[SIR_34:16]

3020 fps out of a 22" barrel with 54.0 gr H4350

 

[Tod osier]

Did some testing in tikka t3x superlite 270win, Norma brass, cci200, h4350 worked up to 56.3gr., seated ogive at 2.765 due to mag length. best group was about .75”. Using magneto speed Chrono, it clocked in from mid to high 2900’s fps. Outside temp was about mid to high 50s. Anyone have similar velocities? Weeks prior I used a Caldwell Chrono and it showed over 3100fps. No pressure signs. Rifle has about 60rounds, never been cleaned.

I'm still working up a load, but I have good accuracy in a t3 superlite, RP brass, cci 200, H4350 at 55.5 grains. I got 3151 with a magnetospeed with no pressure signs.

 

[JFK]

Tikka barrels tend to be very slow. Maybe it’ll speed up with more rounds down the tube? 130gr (or 129gr in this case) bullets should have no problem going north of 3000fps out of any 270.

 

[jzeblaz]

I'd clean the barrel. 60 rounds seems like a lot to me.

 

[Sled]

Yes factory 22” barrel. I was hoping the velocity was up in the 3100 range just like it was when I used my Caldwell Chrono, can’t use it now since the negative battery wire broke off, will weld it back and see if it works. But I used my buddies magneto speed and it stated mid to high 2900’s. Not sure which one is more accurate.

i have both the caldwell and the magneto speed. my magneto speed was very accurate for the first 6 months i owned it, then it started reading high for no reason. i spent a lot of time trying to figure it out. now i just use the caldwell and pay attention to the light conditions.

if you can shoot out past 400-600 yards you should be able to verify your speeds.