300 whisper and 155s at 600 yds

[fastshooter03]

I was checking with Sierra's I5 ballistic software and 155 Lapuas will still be supersonic at 600 yards when loaded to max out of a 10" barrel(1800 FPS). So naturally it would be no problem for a 16" barrel or longer.

Has anybody tried it? Just seems like fun to me. When I shot my Deer last year with full power 300 whisper 125 grn loads the gun barely jumped and muzzle blast didn't even ring my ears.

Elevation requirements are around 30" @100 yds--less for faster loads. Energy will still be around 550 lb fts for those interested.

Nick

[ken hebert]

Gimme a little while and I'll be able to tell you what Sierra 155's do at 500 yards out of a 16" barrel at full power. IIRC, I loaded them to be in the neighborhood of 1650fps. We just pushed my home range out to 500 yards, and I've got some fresh .300 Whisper, 155gn supersonic and 208gn subsonic loads to try out. That, and I'm dying to try out the can.

[Flexmoney]

Is the rifling twist set to stablize those bullets ?

[fastshooter03]

Most 30-221s or Whispers are made with a 1x8 twist barrel to stabilize 240 grn bullets at subsonic speeds. And they are just barely stable. When you hit ANYTHING, including thin particle board, they immediately tumble. I was shooting SS 220s at 200 yds and you could see the bullets hitting to the left and right side of the target but all the holes were in the center of the board. So 155s shouldn't pose any problems being stabilized even with a slower twist.

My friend shot a deer in the neck this past season with his suppressed 30-221 and SS 220s and he said it just let out a moan and dropped dead. He also said the wound channel looked like a meat grinder went through there.

We have a 600 yd match coming up May 25 and I hope to get some results with 155 lapuas and my bolt 30-221.

Can't wait to here what happens Ken. Is 1650 fps the most you can get or just a sweet spot?

Nick

[kgunz11]

Haven't tried any of the lighter bullets out of my GA Precision built Whisper. I had mine built on an AR-15 upper with the Armalite adj gas block so I could choose single fire or repeater. I've slung the 190's with great accuracy in the supersonic range. In my 1/8 twist bbl they don't like the subsonic realm very well. I've got some 240's to try in it next.

[ken hebert]

Most 30-221s or Whispers are made with a 1x8 twist barrel to stabilize 240 grn bullets at subsonic speeds. Can't wait to here what happens Ken. Is 1650 fps the most you can get or just a sweet spot?

Nick

Thats about what my gun likes, any hotter and I start to flatten out or blow out primers. I've not chrono'd that load, spouting numbers according to what my book says it should be. In my gun that's 16.2 gn of H110 with a 155 Sierra Palma Match. Subsonic is a (for now) 208gn A-Max with 9.1gn of H110. I WILL chrono both loads when my can comes in, hate to have to haul all that crap out to the range more that I have to.

edit. mine is a 1-8.

Edited May 23, 2008 by ken hebert

[fastshooter03]

16.5 grns of N110 was blowing out FED match primers with a 155 lapua loaded to 2.200". My bolt gun is not throated for AR mag length. Velocity was around 1900 FPS. Didn't shoot for crap at 100. This was a load off the Sierra Infinity software with the only difference being the shorter load length. WHAT a difference!

Went to RL7 and just for kicks RL10x with the same bullet and length. RL7 went to 2000 FPS with 20grains but the case was bulging from compressing the powder charge. Shot groups around 1.5" at 100. Wind was gusting and swirling. NO signs of pressure.

My load of 18 grains of RL10X went into under and inch with 4 holes touching and a flyer which was very surprising but velocity was only 1700 fps. NO signs of pressure.

My final load for tommorrow was 20.0 grains of RL10x. It fills up the case to halfway up the neck. I found that if you go slow and peck with the seating die you can seat without bulging the case. I'm sure they are SLIGHTLY compressed loads trying to get to 2000fps.

Hopefully I'll have results tommorrow night.

Nick

[kgunz11]

16.5 grns of N110 was blowing out FED match primers with a 155 lapua loaded to 2.200". My bolt gun is not throated for AR mag length. Velocity was around 1900 FPS. Didn't shoot for crap at 100. This was a load off the Sierra Infinity software with the only difference being the shorter load length. WHAT a difference!

Went to RL7 and just for kicks RL10x with the same bullet and length. RL7 went to 2000 FPS with 20grains but the case was bulging from compressing the powder charge. Shot groups around 1.5" at 100. Wind was gusting and swirling. NO signs of pressure.

My load of 18 grains of RL10X went into under and inch with 4 holes touching and a flyer which was very surprising but velocity was only 1700 fps. NO signs of pressure.

My final load for tommorrow was 20.0 grains of RL10x. It fills up the case to halfway up the neck. I found that if you go slow and peck with the seating die you can seat without bulging the case. I'm sure they are SLIGHTLY compressed loads trying to get to 2000fps.

Hopefully I'll have results tommorrow night.

Nick

Sounds like you are crushing powder and that will significantly effect the load making it inconsistent. Some powder crunch is ok, but when the kernels break it changes the burn rate of the powder by exposing more broken and jagged edges.

[JKSNIPER]

Want good stopping/energy dump into the deer?

Load 155 AMAX (T.A.P.) rounds.

They make 'em in 110 grain,155 grain, and 168 grain.

They expand and drop deer like a bad habit.

I have a GA "Rock" rifle (.308) with a Mike Rock 22" barrell.

Shoots like its on FIRE when I manage to do my part.

JK

[kgunz11]

Want good stopping/energy dump into the deer?

Load 155 AMAX (T.A.P.) rounds.

They make 'em in 110 grain,155 grain, and 168 grain.

They expand and drop deer like a bad habit.

I have a GA "Rock" rifle (.308) with a Mike Rock 22" barrell.

Shoots like its on FIRE when I manage to do my part.

JK

JKSNIPER,

Do you have a Whisper or know much about them? Do you know enough about the Hornady AMAX bullet to know what velocity it will have to travel to be effective? The problem with the Whisper is with the heavier bullets you can't get them going fast enough to expand, and without expansion there is very little damage. For deer, a 125 gr ballistic tip will work and you can get it up to speed so the bullet does its job.

[fastshooter03]

Other than the ballistics chart being wrong things went pretty well. The first 3 rounds were low. I saw the second impact and dialed it up accordingly. I ended up with 132 clicks(Approx 34 inches) of elevation on a 100yd zero. Still don't know what the velocity is though. I have some rounds left so I'll chrono them eventually.

Once on paper it stayed there. Almost shot as good as my junk 223 75 grn hornady/Tac load. No vapor trail to see though. I think the targets were some kind of NRA type 600 yd with the paper being tan colored up to the 7 ring and then 7-10x were black. I forgot to measure the target size. They were about twice as wide as an IPSC target and the edges were trimmed to only show out to the 7 ring on the sides and 6 ring on the top so I'm sure the original target is probably about 3 IPSC targets wide. The first 3 rounds after getting on paper were all 10s or 10xs. Then they sorta floated around in the 7,8,9,10s until my 15 rounds where up. It had about the same recoil as my monster AR with brake. I was pretty happy since I haven't cleaned this rifle in over a year as it's more like a long pistol with a big scope

I noticed afterwards that RL10x has about the same burn rate as Benchmark so I could've tried that powder.

They're trying to put together another 600 yd in June so I'm definitely going to try it again with some other load. Maybe look for a lighter bullet with a decent BC.

Nick