155gr palmas

[mao0720]

Im just wondering what kind of velocity I can get with the 155 gr SMK palmas out of a 30" barrel using varget or similar powder? My reloding manual says about 2909 out of a 24" barrel, just curious what the velocity increase would be out of a 30" Thanks!

 

[ar15topgun]

2950 to 3000 or so. Your case choice and bore diameter will factor into this equation.

 

[Bob3700]

Lapua brass is heavier than Winchester so if you are after top FPS the Winchester brass has more boiler room.

With either brass, you should be able to get 2950 from a 30 inch tube.

Bob

 

[mao0720]

Im have some Lapua and some Winchester brass. I was planning on using the Lapua for these loads. I just ordered 300 of the 155gr palmas from Midsouth for my new rifle that should be done by the end of the month. Its a Savage Dual port target action, Krieger 30" LV barrel, and *gasp* bedded into a choate tactical stock (the A5 style one not the crazy "ultimate sniper" one.

 

[spclark]

30" ought to be good for 2950 - 3000 fps with a proper "Palma" chamber & the 155 bullets out there now with Varget, N150 or H4895.

I get 3025 safely with IMR8208XBR in Lapua brass in one 30" barrel where the same load in a different one of only 29" gives me 2975. Both barrels are x-ring accurate @ 1,000 yards when I pay attention to the wind.

 

[Keith Glasscock]

I agree. 2950-3000 at sane pressures with the shorter throat. You can get a bit more at "max," but I don't think accuracy is as good. On the other hand, longer throat do provide e little more boiler room, and thus, more velocity.

 

[mao0720]

Cool, the reamer being used to cut my chamber is apparently cut so that Factory FGMM 175gr ammo (which is loaded to magazine length) has a .02 jump to lands, so I should have a little more room in the case.

What about those of you using N 540, or N 550? How do you like this powder? Temp sensitive? Accurate? Good velocity?

 

[CZ550]

Try 8208 works really well with 155.5s

 

[spclark]

I've used both but prefer something less costly like H4895 or IMR8208 XBR. The -40 series propellants seem to be a little more temp-sensitive than the -50 series, either 1xx or 5xx.

In my barrels the 2155 and 2156 both shot great jumped 0.020". When I started in with Berger's 155 Hybrid that's where I began in load testing too.

Later in competition (2012 with my newest Palma rifle, the 29" Bartlein 1:12) I saw nothing to indicate a need to change.

 

[Romulus]

I've seen a few buildups of XBR with 155s deliver great chrono stats and accuracy - 2156 and Hybrids.

 

[Steve Blair]

My 26" tactical .308 gets oustanding velocity and accuracy with 8208 XBR and Berger 155.5 FULLBORE bullets. My experience with this combo is far from unique.

 

[mao0720]

SPClark, can I use the n150/n550 with the 155s? Everything I've seen says that those powders are for heavier bullets.

 

[spclark]

SPClark, can I use the n150/n550 with the 155s? Everything I've seen says that those powders are for heavier bullets.

A cautious yes on that question. They might be better used with heavier bullets (I've used N550 with 185's with great results) but they have a place with 155's too when Nx40's show temperature issues.

Attachment is excerpted from a VV manual; I highlighted the charge weight columns in green that are given in grains.

All reloading disclaimers apply of course! You need to work up an accurate and safe load with your equipment and shooting practices.

 

[mao0720]

Anybody care to share any recipes for the 155s and varget or IMR 4895? Im using this rifle for FT/R so I need to be supersonic at 1000 yds.

 

[Heman]

My load for the 2155 is 47.5gr of Varget in LC07 LR brass turned, Wolf LRM primer, bullets are molly coated. Chamber is cut for the 185gr LRBT so I got the boiler room. Speed is north of 3,000 but they shoot really nice at 600yds and will be supersonic. Never shot them for palma becasue I shoot the 185's there. If you have at least a 12 twist save yourself some points and shoot the Berger 185gr LRBT (now Juggernaught) at 1k heck of a bullet.

 

[Bamban]

Would anyone be willing to share their 8208 loads with the 155 Palmas?

TIA

 

[broncman]

47 grains of Varget get me 3020 in winchester cases, 30" factory savage.

 

[mao0720]

Damn thats a lot of powder for a 308. Any pressure warnings at all?

 

[NateG]

Damn thats a lot of powder for a 308. Any pressure warnings at all?

Depends on the lot of Varget. I know of some folks with slow lots running over 47 grains and wishing they had more capacity to stuff more in. I've also seen faster lots who couldn't go anywhere near that charge...

And regarding 8208, I've used from 44.0 to 44.5 grains, with 2156s and Berger 155 Hybrids. (and both Lapua Palma and standard Lapua cases)

 

[broncman]

Damn thats a lot of powder for a 308. Any pressure warnings at all?

With winchester cases and cci br primers, no. Federal cases gave me ejector marks. Had to back off. The palmas set way up in the neck as well.

I had some Sierra 110 varmints that I tried with 47 grains and wlr primers..they peirced 2 primers and I pulled the rest. CCI BR primers were good in that load and extremely accurate!