|
Joined: Feb 2007
Posts: 16,512
Campfire Ranger
|
OP
Campfire Ranger
Joined: Feb 2007
Posts: 16,512 |
First, I want to say this is not to argue that the 120 is not effective, it is, but it's an exercise of 'ballistic gack' - Doberism My impetus for this exercise, is b/c so many 7/08 users rave on the 120 (not a bad choice mind you, but I don't see the 'benefit' in common std. chambers). Do note I have shot my share of 7/08 rifles, from 100-160gr bullets. I do like the round. Below is comparing typical speeds in 7/08 std. chamber using 120/140 BTs and a comparison w/Dogzappers rifle: 7/08 AI using 120s. Here is how the numbers crunch: 7/08 Std. chamber - 140 Ballistic tip at 2950: Muzzle -1.5 2950 2705 100 1.5 -6 2758 2364 200 0.0 0 2574 2059 300 -6.8 9 2398 1787 400 -19.7 19 2230 1545 500 -39.5 30 2067 1329 7/08 AI - 120 gr Ballistic tip at 3255mv: Muzzle -1.5 3255 2823 100 1.2 -4 3017 2425 200 0.0 0 2791 2075 300 -5.6 7 2576 1768 400 -16.5 16 2372 1499 500 -33.6 26 2178 1264 10mph Wind deflection at 400 yds: 11.3" for 120/3255 10.9" for 140/2950 Let's compare a 7/08 standard chamber - 120/3050 mv Muzzle -1.5 3050 2479 100 1.4 -5 2822 2122 200 0.0 0 2606 1809 300 -6.6 8 2400 1535 400 -19.2 18 2205 1296 500 -39.0 30 2018 1085 Wind 10mph at 400 yds: 12.3" Therefore in a std. chamber, I'd rather use a 140 vs. 120 b/c: Using a 140/2950 vs. a 120/3050 will cost you 1/2" of drop ONLY at 400 yds, and GAIN 250 lbs energy, and drift is 2.4" LESS by using the 140gr. I hope that clears up some thoughts on 120 vs. 140 in the 7/08 - assuming standard chambers. Ballistically speaking, I just don't see the advantage of 120s myself. This however does not mean to negate the deadliness of the 120 Btip and TSX/TTSX at typical speed and ranges, as they do kill just fine. The outcome will be the same as Dogzapper says, 'Dead is Dead' and that is true. Now if using an AI, the increase in speed over a std. chamber, I believe is greater using a 120 vs. a 140 due to their modest capacity (as a say 280 or 7RM would be more efficient - in a sense, w/heavier bullets, due to more powder). SO, the compelling reason for a 120 in a 7/08 - assuming at AI speed - is created - IMHO. No doubt, as always when crunching numbers, one can play w/#'s a little either way, but suffice to say before flames begin, the small differences of input/ouput in a ballistics calculator are not going to drastically change the analysis, IMO. Now that's settled, I need to get my new custom 6.5s done as soon as McM ships my stocks so I can spit some 130 ABs downrange! LOL.
|
|
|
|
Joined: Jun 2004
Posts: 44,893 Likes: 12
Campfire 'Bwana
|
Campfire 'Bwana
Joined: Jun 2004
Posts: 44,893 Likes: 12 |
What a lot of 120 users like is its thicker jacket.
|
|
|
|
Joined: Oct 2004
Posts: 25,844
Campfire Ranger
|
Campfire Ranger
Joined: Oct 2004
Posts: 25,844 |
My dog is a member of the "Turd Like Clan"
Covert Trail Cameras are JUNK
3 Time Dinkathon Champion #DinkGOAT
|
|
|
|
Joined: Feb 2007
Posts: 16,512
Campfire Ranger
|
OP
Campfire Ranger
Joined: Feb 2007
Posts: 16,512 |
I get it that the jacket is 'thick' for a light bullet and it penetrates well, but is that 120 jacket 'THICKER' than the 140 version? NO doubt it's a performer, I just like the extra energy and wind drift advantage at a 1/2" price in trajectory at 400 yds using a 200 yd sight in.
Personally I'd pick a std. 139 or better yet, 140 Accubond, expecting better penetration w/the 140 AB, not necessarily needed w/o hitting heavy bone. But one step up, I think the 120 TSX and TTSX 'offer' more penetration potential than any of the above bullets, assuming normal ranges/speeds.
|
|
|
|
Joined: Nov 2002
Posts: 21,826 Likes: 3
Campfire Ranger
|
Campfire Ranger
Joined: Nov 2002
Posts: 21,826 Likes: 3 |
I get it that the jacket is 'thick' for a light bullet and it penetrates well, but is that 120 jacket 'THICKER' than the 140 version? Yes. Ballistic Tip 120 Design was altered for Silly-Whette shooters (Long story, Dogzapper has related several times). AND it kills stuff every effectively. BMT
"The Church can and should help modern society by tirelessly insisting that the work of women in the home be recognized and respected by all in its irreplaceable value." Apostolic Exhortation On The Family, Pope John Paul II
|
|
|
|
Joined: Feb 2007
Posts: 16,512
Campfire Ranger
|
OP
Campfire Ranger
Joined: Feb 2007
Posts: 16,512 |
BTW, IF the 120 was developed after the original 140 BT, OR re-designed, it may well have a thicker jacket than the original 140. No doubt Noz changed things in their BT line up as the .277 130 BT was said to be 'soft' upon intro from what I am told, though I never had any issues w/150s - my rifles just preferred the heavier BTs in accuracy.
Maybe somebody KNOWS the latest facts on jacket thickness in 7mm BTs, the 120 vs. 140. My guess is today's production - they are the same. I could be wrong.
That said, the 120 BT is the ONLY cup/core 120gr 7mm I'd fire at deer or larger game. Yet, when I want a 140 bullet, the BT is not going to be my choice, I'd rather an Accubond over the BT and I guess a case can be made for tougher bullets yet if one wants to take really large game with one.
Again, not to say there are many flies on the proven 120 BT, but the 'math' just does not compel me.
|
|
|
|
Joined: Feb 2007
Posts: 16,512
Campfire Ranger
|
OP
Campfire Ranger
Joined: Feb 2007
Posts: 16,512 |
I get it that the jacket is 'thick' for a light bullet and it penetrates well, but is that 120 jacket 'THICKER' than the 140 version? Yes. Ballistic Tip 120 Design was altered for Silly-Whette shooters (Long story, Dogzapper has related several times). AND it kills stuff every effectively. BMT BMT, no doubt, I recognize they work, and why it was changed. I guess what would be interesting enough, would be a penetration and wound channel comparison of say: 120 BT 140 BT 120 TSX/TTSX 140 AB 140 TSX Do you guys that like and use the 120 BTs feel 100% confident if you had a 'bad angling' shot or hind end shot on a large deer or elk? Curious. Myself, I'd rather either the TSX/TTSX or a good 140 for 'insurance' if I must drive really deep or thru heavy bone. That's more a reason to me than 250 lbs or a dope advantage.
|
|
|
|
Joined: Jun 2004
Posts: 44,893 Likes: 12
Campfire 'Bwana
|
Campfire 'Bwana
Joined: Jun 2004
Posts: 44,893 Likes: 12 |
I don't hunt elk, and I would (and have) passed on ass end shots on deer. But that's my preference no matter the cartridge/bullet I'm using.
If I absolutely had to shoot one from the back end, then I'd first concern myself with busting up the "rear axle" to immobilize.
|
|
|
|
Joined: Dec 2007
Posts: 16,172 Likes: 9
Campfire Ranger
|
Campfire Ranger
Joined: Dec 2007
Posts: 16,172 Likes: 9 |
First, I want to say this is not to argue that the 120 is not effective, it is, but it's an exercise of 'ballistic gack' - Doberism My impetus for this exercise, is b/c so many 7/08 users rave on the 120 (not a bad choice mind you, but I don't see the 'benefit' in common std. chambers). Do note I have shot my share of 7/08 rifles, from 100-160gr bullets. I do like the round. Below is comparing typical speeds in 7/08 std. chamber using 120/140 BTs and a comparison w/Dogzappers rifle: 7/08 AI using 120s. Here is how the numbers crunch: 7/08 Std. chamber - 140 Ballistic tip at 2950: Muzzle -1.5 2950 2705 100 1.5 -6 2758 2364 200 0.0 0 2574 2059 300 -6.8 9 2398 1787 400 -19.7 19 2230 1545 500 -39.5 30 2067 1329 7/08 AI - 120 gr Ballistic tip at 3255mv: Muzzle -1.5 3255 2823 100 1.2 -4 3017 2425 200 0.0 0 2791 2075 300 -5.6 7 2576 1768 400 -16.5 16 2372 1499 500 -33.6 26 2178 1264 10mph Wind deflection at 400 yds: 11.3" for 120/3255 10.9" for 140/2950 Let's compare a 7/08 standard chamber - 120/3050 mv Muzzle -1.5 3050 2479 100 1.4 -5 2822 2122 200 0.0 0 2606 1809 300 -6.6 8 2400 1535 400 -19.2 18 2205 1296 500 -39.0 30 2018 1085 Wind 10mph at 400 yds: 12.3" Therefore in a std. chamber, I'd rather use a 140 vs. 120 b/c: Using a 140/2950 vs. a 120/3050 will cost you 1/2" of drop ONLY at 400 yds, and GAIN 250 lbs energy, and drift is 2.4" LESS by using the 140gr. I hope that clears up some thoughts on 120 vs. 140 in the 7/08 - assuming standard chambers. Ballistically speaking, I just don't see the advantage of 120s myself. This however does not mean to negate the deadliness of the 120 Btip and TSX/TTSX at typical speed and ranges, as they do kill just fine. The outcome will be the same as Dogzapper says, 'Dead is Dead' and that is true. Now if using an AI, the increase in speed over a std. chamber, I believe is greater using a 120 vs. a 140 due to their modest capacity (as a say 280 or 7RM would be more efficient - in a sense, w/heavier bullets, due to more powder). SO, the compelling reason for a 120 in a 7/08 - assuming at AI speed - is created - IMHO. No doubt, as always when crunching numbers, one can play w/#'s a little either way, but suffice to say before flames begin, the small differences of input/ouput in a ballistics calculator are not going to drastically change the analysis, IMO. Now that's settled, I need to get my new custom 6.5s done as soon as McM ships my stocks so I can spit some 130 ABs downrange! LOL. While you can yap about numbers all you want, it's all just conjecture while looking in the book for results. My 22" runs 140's at 2950, but runs 120 BT's at 3175 and shoots little knots out to 500. So the "superior" advantage of the 140's is flushed right down the [bleep].......
|
|
|
|
Joined: Apr 2005
Posts: 30,987 Likes: 7
Campfire 'Bwana
|
Campfire 'Bwana
Joined: Apr 2005
Posts: 30,987 Likes: 7 |
I don't hunt elk, and I would (and have) passed on ass end shots on deer. But that's my preference no matter the cartridge/bullet I'm using.
If I absolutely had to shoot one from the back end, then I'd first concern myself with busting up the "rear axle" to immobilize. A very wise choice of shot location with any bullet
I got banned on another web site for a debate that happened on this site. That's a first
|
|
|
|
Joined: Feb 2007
Posts: 16,512
Campfire Ranger
|
OP
Campfire Ranger
Joined: Feb 2007
Posts: 16,512 |
WOW, what powder are you using? Your speeds are well above what I have seen and obtained.
Can you 'quantify' in more specific terms how 'inferior' a 7mm 140gr at 2950 is then a 7mm 120 at 3175?
Running #s -
I see the 140 load needs 30 clicks vs. 27 clicks of come up w/a 200 yd zero, at 500 yds.
The 140 load needs 13 clicks windage for 10mph, the 120 needs 14.
The 140 has fps/lbs 2067 1329.
The 120 has fps/lbs 2116 1192.
SO Aalf, it looks like you get 3 clicks advantage of elevation using a 120 gr, 1 click disadvantage on windage, and a REDUCTION of 137 lbs of energy.
|
|
|
|
Joined: Jan 2008
Posts: 7,722
Campfire Outfitter
|
Campfire Outfitter
Joined: Jan 2008
Posts: 7,722 |
I don't use the 120 cause I think it's "better"....nor does the study make me think it's much worse either. I tried the 120's and work good so I've kept shooting them.
|
|
|
|
Joined: Jan 2008
Posts: 7,722
Campfire Outfitter
|
Campfire Outfitter
Joined: Jan 2008
Posts: 7,722 |
At 500 yards I'm my biggest disadvantage......grin.
|
|
|
|
Joined: Oct 2009
Posts: 1,478
Campfire Regular
|
Campfire Regular
Joined: Oct 2009
Posts: 1,478 |
WOW, what powder are you using? Your speeds are well above what I have seen and obtained. Thought it was just me.
|
|
|
|
Joined: Feb 2002
Posts: 13,672 Likes: 1
Campfire Outfitter
|
Campfire Outfitter
Joined: Feb 2002
Posts: 13,672 Likes: 1 |
I get it that the jacket is 'thick' for a light bullet and it penetrates well, but is that 120 jacket 'THICKER' than the 140 version? Googles your friend. Stole from another site, but pretty sure it's been posted here as well. FWIW, I remember some time back, a poster from TX was switching from using the 120s to the 140s because the 120s didn't open as fast out of his 7mm Rem Mag...
|
|
|
|
Joined: Feb 2007
Posts: 16,512
Campfire Ranger
|
OP
Campfire Ranger
Joined: Feb 2007
Posts: 16,512 |
Kaleb, no doubt it's close enough to call awash, no big +/- either way - so I too see them as ballistic twins. Thanks for the pic, googled this one up to: http://www.flickr.com/photos/40165144 N04/3701055916/ <a href="http://www.flickr.com/photos/40165144 N04/3701055916/" title="cross sections by baldhunter, on Flickr"><img src="http://farm3.static.flickr.com/2664/3701055916_058f4ae6f4.jpg" width="500" height="375" alt="cross sections"></a> The 140 AB looks a little sturdier yet. Nice someone did the sectioning. Re-inforces my pick of the 140 AB. Thanks for the 'google images' reminder And yet another pic.. http://media.photobucket.com/image/...n/Shooting/120bt150bt140ab168bt180bt.jpgYep, looks like the 120 is thicker esp. in the nose to 'control initial expansion' which far better than using say a Vmax...no doubt each having a different intended use. As I said, its no doubt the best pick for say deer in a 120 Cup/core, assuming you are choosing a 120. Thanks for the viewpoints to all.
|
|
|
|
Joined: Dec 2008
Posts: 5,185
Campfire Tracker
|
Campfire Tracker
Joined: Dec 2008
Posts: 5,185 |
I don't use the 120 cause I think it's "better"....nor does the study make me think it's much worse either. I tried the 120's and work good so I've kept shooting them. Our own experiences are the best teacher. However, it's good to know others get similar results. Dogzapper has posted very good results and I'm a Tim fan, so I'm good to go.
Last edited by CLB; 08/19/11.
|
|
|
|
Joined: Feb 2004
Posts: 2,244
Campfire Regular
|
Campfire Regular
Joined: Feb 2004
Posts: 2,244 |
I shoot the 120x....not tsx or ttsx....As with only +/-100 critters, from 265# wt to a 5# nutria, have yet to find a bullet....When I run outta 120x's then I've got 1500-2000 Tsx's to shoot....for my needs the 120's do great....One wt deer took 2 shots to do him in, but that was cuz he was running wide open in front of some dogs and a poor shot was made on the first one...YMMV.....
George
"Hunting, fishing, roping, working, sleeping, eating. Not always in that order."
|
|
|
|
Joined: Jan 2003
Posts: 4,070
Campfire Tracker
|
Campfire Tracker
Joined: Jan 2003
Posts: 4,070 |
Cliff, my main turn off with the 140NBT is its explosive characteristics when it strikes heavy bone. The 120NBT has proven itself to NOT demonstrate this. Quicker opening than the accubond, yes. But it do penetrate. Double shoulder shot at 225 and it was on its way out. Tad more meat damage than the accubond, but very serviceable. In the 7-08, I have not seen a bullet take a WT off its feet faster than the 120NBT. Now if I'm driving the good ol 280AI, the 140AB is the only bullet I'd consider. And if I were to twist another 7-08AI, I dont know if I'd go 140NAB or 120NBT. My fav in that particular caliber is no longer made. My old 7-08AI had a thing for the 140XLC. 26" tube produced 3185fps with that bullet. No pressure signs but I would not hesitate to agree with anyone that said I got a fast barrel. Was a Douglas on that rifle. But anyway, thats my take on things.
Crossed Arrows Archery LLC Authorized Obsession Bows Dealer Custom Strings/Tuning www.crossedarrowsarcheryllc.comBlack Eagle Arrows Pro Staff, Montana Black Gold Shooting Staff, Dead Center Archery Products Shooting Staff
|
|
|
|
Joined: Dec 2002
Posts: 4,474
Campfire Tracker
|
Campfire Tracker
Joined: Dec 2002
Posts: 4,474 |
Ramshot Big Game will get you in the 3200 fps. neighborhood with the 120 BT, been discussed at length in the reloading section.
|
|
|
|
524 members (1_deuce, 17CalFan, 1234, 1936M71, 10gaugeman, 12344mag, 51 invisible),
1,756
guests, and
1,121
robots. |
Key:
Admin,
Global Mod,
Mod
|
|
Forums81
Topics1,194,105
Posts18,522,468
Members74,026
|
Most Online11,491 Jul 7th, 2023
|
|
|
|