7mm 120BT : Good penetration?

roysclockgun

Handloader
Dec 17, 2005
736
1
On one mule deer, one white tail deer, two wild hogs and one pronghorn, the 140AB performed well in my 280Rem. chambered Browning Stalker. I did, however, want a flatter trajectory, so rather than load the 140AB above my load of 53gr. IMR4350, I decided to go to the 120BT! Last year's pronghorn was shot at 276 yards and my 140AB bullet dropped enough to only sever his fore leg and skin his chest. After chasing the three legged pronhorn, I held higher at about the same range and dispatched him. I dislike not making clean, one shot kills.
I had some Nosler 120BT for my wife's 7mm-08, so I loaded up enough for a good test, along with some 120gr. Sierra SP. With both bullets, I loaded 57gr. IMR4350. The book says hat load should go out the muzzle at over 3200fps, but I will Chrony the load next wee.
Weighing the Nosler against the Sierra out to 300 yards was, as I found out, not really a fair comparison. This, because beyond 200 yards, the boat tail Nosler must fly better than does the flat base Sierra.
For the test, I did not touch the BOSS, which had been dialed in for the 140AB and with that bullet, was consistantly printing four rounds into one small, ragged hole at 100 yards.
The day was overcast, with a mild wind and the temperature was in the high 70s.
I zeroed the 120gr. bullets to print 3" high at 100 yards. Both the Sierra and Nosler kept 3/4" groups in the same spot on the target. Moving out to 200 yards, both printed 1 1/2" high and held well within 2" groups.
It was at 300 that the Nosler really outshown the Sierra, as the Nosler group was 3 1/2" low, while the Sierra printed 6" low. Surprisingly, both held 2 1/2" groups at 300, which may mean that I had settled down more, shooting off the sled, than I was at 200 yards.
Next week I will use the Chrony and report on MV.
Question : Has anyone had experience using the 7mm Nosler 120Ball.Tip. on heavy bucks out to 300 yards? Can I expect good, acceptable penetration at that range, or not?
Best,
Steven in DeLand, FL
 
I've used the 120gr NBTs with good results(only 2 deer), pass thrus, on WTs out of a 7mm-08. I loaded these for a reduced-recoil load. Load was mild, 2865fps, but this is where I like to use the BT on big game anyways. Shots were broadside, no shoulders, and were 65 and 105 yds. Different than your application but I think at 300 yds you'd be seeing similar impact velocities.

Personally, I think the 140gr NAB is perfect for Pronghorns at the distances you describe from your 280Rem. It looks like that would put you in the 2850-2900fps range. A +2.5"@100yd zero should put you around -3.8"@300yds.

I've played with the numbers for the 140NAB in a 270Win alot and found them to be very easy to re-produce and efficient. Very similar to the velocity that you are using. They should hold against the wind a bit better than the 120gr NBT too.
 
7mm -08 on a buck at 20-30 yards.

MV=3050 fps. Thought both shoulders found in far hide.


SV101529.jpg



SV101528-1.jpg


It is a micrograph of the 140 gr BT
 
just fyi, nosler uses the same jacket cup on the 120's they use for the 140's so it ends up with a thicker jacket, it'll be fine.
RR
 
Looks like JD338 posted a test on this very bullet, and there's some useful commentary as well:

viewtopic.php?f=49&t=16495

I can see the value of a fairly light, fast bullet for the pronghorn & mule deer hunt - heck, I'm likely taking my .25-06, and your .280 is just a grown-up version of that! :grin:
 
The 120 gr BT should work fine, even on a big buck but I would opt for the heavier 140 gr BT or AB. It will give you more penetration on a quartering shot and it will buck the wind better.

JD338
 
My wifes 7-08 shot them really well. Took several bucks out to 150 yards and several does out to 300 yards. They were smoking along at 3150 according to my chrony. I shot this bear with three 120bt out of my 280ai doing roughy the same speed at 388 yards twice, and once at ten yards . Have yet to recover a single one.
View attachment IMG-20110910-00152.jpg
 
You will get some good penetration with it but I've owned a few 7mm's of different types and the bullet i always went back to was the 140 gr ballistic tip. Excellent penetration, trajectory, stability, etc etc. And yes, that included a 7mm-08. It shot the best with a 140. Actually they all performed best with a 140. This includes the odd eight, Rem Mag, and even the STW.

They would perform alright and acceptable with 120 gr to 160gr, but the best was always the 140's.
 
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