7mm-08 120 TTSX vs 308 130 TTSX

[S3silver]

I own several 308 bolt action rifles and just acquired a 7mm-08 barrel to screw onto a Savage action. Was researching and pondering the advantages and disadvantages of each for hunting and seems like they are pretty much neck to neck. The criteria would be 500 yards or less, shooting 130 ttsx out of the 308 and 120 ttsx out of the 7mm-08. I currently get 3150 out of my 308 with the 130 ttsx. Google says 7mm-08 users are getting the same out of the 120 ttsx in a 7mm-08. More frontal with 308 but better BC with 7mm (.373 vs .350). Out to 500 it probably doesn't even matter which one to use as they will probably both be bang/flop. I know it will probably come down to personal preference and what you already have but it's always fun to hear other people's rationale.

What would you choose and why?

 

[Orr89rocz]

7 cuz you already have 308’s. Good to have variety. Cant go wrong either way. I like the 7-08. I dont have one yet. I have a 308 but dont shoot light bullets. I wanted to try the lighter ones but need a different gun to do it in

 

[ben-o]

It’s less of a problem now, but 308 brass is easier to get than 7mm-08 during a shortage. Otherwise, there’s not much difference. Maybe a little less recoil with the 120 grain bullet, especially if you don’t go for max velocity.

 

[Larryh128]

Flip a coin, I load 130 TTSX in a 308 for my grandson, bang , flop.

 

[dfrosch]

I own several 308 bolt action rifles and just acquired a 7mm-08 barrel to screw onto a Savage action. Was researching and pondering the advantages and disadvantages of each for hunting and seems like they are pretty much neck to neck. The criteria would be 500 yards or less, shooting 130 ttsx out of the 308 and 120 ttsx out of the 7mm-08. I currently get 3150 out of my 308 with the 130 ttsx. Google says 7mm-08 users are getting the same out of the 120 ttsx in a 7mm-08. More frontal with 308 but better BC with 7mm (.373 vs .350). Out to 500 it probably doesn't even matter which one to use as they will probably both be bang/flop. I know it will probably come down to personal preference and what you already have but it's always fun to hear other people's rationale.

What would you choose and why?

Is that a Savage factory barrel? If so, check your twist rate. They made both 9.5 and 11.5 twists. The 120 TTSX might shoot through both, but it'll probably like the 9.5 twist better.

 

[IMR4064]

7mm will have less recoil, but 308 components are more available.

 

[S3silver]

The barrel I have is a 26” McGowen varmint contour 9 twist. It’s my first 7mm-08 but I also have two 284 win and a 7 mag. If it shoots good might get another in a lighter contour for hunting. Really hoping it goes bang flop like my 308’s.

 

[Zero333]

22" barrel chambered for the 7mm-08 will spit out the 120 TTSX at around 3,000 fps which is almost 2,500 lb-ft of muzzle energy and will drift 24" at 500 yards in a 10 mph 90 degree cross wind.

22" 308win shooting 130 TTSX will get you 3,050 fps and almost 2,700 lb-fts at the muzzle and drift 23" at 500 yards in a 10 mph crosswind.

NECK AND NECK...

I have a 7-08 and 308win hunting rifles that are EXACTLY the same in weight etc... I use whichever one I happen to dig out of the safe first.

However.. with the 308win, you can use 110 TTSX that will fly much flatter than the 7mm 120 TTSX.

Another thing I will add.. because both my 7-08rem and 308win rifles are identical, I can NOT tell any difference whatsoever in recoil.

 

[searcher]

I own several 308 bolt action rifles and just acquired a 7mm-08 barrel to screw onto a Savage action. Was researching and pondering the advantages and disadvantages of each for hunting and seems like they are pretty much neck to neck. The criteria would be 500 yards or less, shooting 130 ttsx out of the 308 and 120 ttsx out of the 7mm-08. I currently get 3150 out of my 308 with the 130 ttsx. Google says 7mm-08 users are getting the same out of the 120 ttsx in a 7mm-08. More frontal with 308 but better BC with 7mm (.373 vs .350). Out to 500 it probably doesn't even matter which one to use as they will probably both be bang/flop. I know it will probably come down to personal preference and what you already have but it's always fun to hear other people's rationale.

What would you choose and why?

I don't shoot either calibers with the TTSX, but do shoot a lot of them in .257 Roberts, 7 MM Rem Mag and .375 H&H. My friends shoot them in your caliber and, from what experience I have seen, it is kind of a trade-off when going to the faster/slower moving bullets in TTSX. With my 7 MM Mag, for example, it is moving along with the 120 TTSX at around 3,550 fps. The hydrostatic shock is enormous within several hundred yards and the deer and pigs I have shot dropped right there. I've seen the "slower" 7 MM's with the same bullet not do as well, with animals running off (a few not recovered), despite lethal hits (mostly pigs). We haven't recovered bullets - so all were pass-through shots, both slow and fast. I think once you slow that bullet down, you lose a lot of the benefit of hydrostatic shock knocking them "senseless", as that would apply to a lot of different bullets as well. If I had the choice at 500 yards with that bullet, I'd choose the .30 Cal. If shooting the 7mm, I'd step up to the 140 or 150, preferably the 150. The BC's are not all they seem with the lead-free bullets either. The comparisons are true for "at the muzzle" velocities, but the lead-free shed velocity faster and the BC's are not equal down range. I think, the further you shoot, the more I'd want the heavier bullets for that reason. If you were to do most shooting within 300 yards - I'd go 120 - beyond that, I'd step it up heavier. Some of the varmint bullet manufacturers list two BC's for a given bullet at different velocities for this reason.

 

[S3silver]

22" barrel chambered for the 7mm-08 will spit out the 120 TTSX at around 3,000 fps which is almost 2,500 lb-ft of muzzle energy and will drift 24" at 500 yards in a 10 mph 90 degree cross wind.

22" 308win shooting 130 TTSX will get you 3,050 fps and almost 2,700 lb-fts at the muzzle and drift 23" at 500 yards in a 10 mph crosswind.

NECK AND NECK...

I have a 7-08 and 308win hunting rifles that are EXACTLY the same in weight etc... I use whichever one I happen to dig out of the safe first.

However.. with the 308win, you can use 110 TTSX that will fly much flatter than the 7mm 120 TTSX.

Another thing I will add.. because both my 7-08rem and 308win rifles are identical, I can NOT tell any difference whatsoever in recoil.

Thanks for the real life comparison between the two. That's what I figured also - neck and neck with each other. I appreciate the additional information regarding recoil. Seems like that's a toss up also.

 

[S3silver]

I don't shoot either calibers with the TTSX, but do shoot a lot of them in .257 Roberts, 7 MM Rem Mag and .375 H&H. My friends shoot them in your caliber and, from what experience I have seen, it is kind of a trade-off when going to the faster/slower moving bullets in TTSX. With my 7 MM Mag, for example, it is moving along with the 120 TTSX at around 3,550 fps. The hydrostatic shock is enormous within several hundred yards and the deer and pigs I have shot dropped right there. I've seen the "slower" 7 MM's with the same bullet not do as well, with animals running off (a few not recovered), despite lethal hits (mostly pigs). We haven't recovered bullets - so all were pass-through shots, both slow and fast. I think once you slow that bullet down, you lose a lot of the benefit of hydrostatic shock knocking them "senseless", as that would apply to a lot of different bullets as well. If I had the choice at 500 yards with that bullet, I'd choose the .30 Cal. If shooting the 7mm, I'd step up to the 140 or 150, preferably the 150. The BC's are not all they seem with the lead-free bullets either. The comparisons are true for "at the muzzle" velocities, but the lead-free shed velocity faster and the BC's are not equal down range. I think, the further you shoot, the more I'd want the heavier bullets for that reason. If you were to do most shooting within 300 yards - I'd go 120 - beyond that, I'd step it up heavier. Some of the varmint bullet manufacturers list two BC's for a given bullet at different velocities for this reason.

You make a good point about losing hydrostatic shock when you don't push the ttsx fast enough. The .30 will have the advantage in frontal area for maximum shock factor.

 

[ChrisNZ]

IMO, TTSX and long range shooting shouldn't be in the same sentence. The two combos you mention are at best a 350yd proposition with std length barrels and less with short ones like my 16" 7-08. It kills like the hammer of Thor up to 250yds but beyond 300, the bullet doesn't open up that much so effectiveness is noticeably reduced. I get 2930 with the 120 in that 16". I have only recovered six of these out of all the deer (and a few pigs) I've shot. The vast majority exit.

 

[Zero333]

Thanks for the real life comparison between the two. That's what I figured also - neck and neck with each other. I appreciate the additional information regarding recoil. Seems like that's a toss up also.

It truly is a toss up except for factory ammo availability the 308win WINS.

Also the 308win has more reloading components available... more brass and more projectiles.

 

[ebb]

Try both and shoot the one that you group the best with. It will give you more confidence. Ballistically they are so close as to be a non issue.

 

[nakneker]

Great bullet, no wrong choice between the two. Rifles I have experience with Barnes either like them or hate them as far as accuracy, I’d do exactly what ebb mentioned above and try them both and then use whatever bullet/rifle combo proves more accurate. Barnes are great bullets, we have two rifles we’ve used them in for years with great results, we’re shooting the TSX but the TTSX is just as good, better if you like the polymer tip.

 

[flatlander]

I ordered a set of 7-08 Improved 30* finisher & resize reamers several years ago, and have built one rifle using that chamber since. It's on a trued Rem M700 action/PTG custom bolt, with a 26" Krieger 1-9tw in sendero contour, in a B&C #2015 stock, which is factory inletted for M5 DBM. I'd bought several bags of WW 7-08 brass probably at least 6yrs ago for this project, and have fireformed a good deal of it, but have also used Starline 308 Match & Peterson 308 Match, both of which have small rifle primer pockets. It's pretty easy to prep 308 cases for fire form loads - I just neck them down but leave a short section of the neck unsized, which creates a 'false shoulder' for fire form loads. I've never compared the straight WW7-08 case capacity to that of the improved version, but it's probably no more than an additional 4-5grs.- it was just one of those projects that I'd always wanted to try. It's a good shooting rifle, but my favorite bullets for it - Sierra 160TMK - are practically unobtanium. It's usually no problem finding 7mm S168MKs, and I've shot quite a few of them in this rifle, with good accuracy at 600yds. It's too heavy a rifle for hunting, weighing in at just over 14lbs with a bipod, but that makes for a very comfortable rifle to shoot extended range sessions, especially when shot with a TBAC Ultra 7 suppressor.

I've thought about building a hunting rifle in this chambering, since I have a Krieger #5 sptr 7mm blank, again in 1-9tw. It's probably overkill for our western Kansas whitetail or mulies , but then again, I've seen some pretty big bucks in a good year when we get adequate rains for good browsing. I would probably use Sierra 140BTSPs, just because I've got a few boxes of them, but there's also Sierra 165 Game Changers that would be better if I wanted to take a longer shot.

 

[tthomp302]

I ordered a set of 7-08 Improved 30* finisher & resize reamers several years ago, and have built one rifle using that chamber since. It's on a trued Rem M700 action/PTG custom bolt, with a 26" Krieger 1-9tw in sendero contour, in a B&C #2015 stock, which is factory inletted for M5 DBM. I'd bought several bags of WW 7-08 brass probably at least 6yrs ago for this project, and have fireformed a good deal of it, but have also used Starline 308 Match & Peterson 308 Match, both of which have small rifle primer pockets. It's pretty easy to prep 308 cases for fire form loads - I just neck them down but leave a short section of the neck unsized, which creates a 'false shoulder' for fire form loads. I've never compared the straight WW7-08 case capacity to that of the improved version, but it's probably no more than an additional 4-5grs.- it was just one of those projects that I'd always wanted to try. It's a good shooting rifle, but my favorite bullets for it - Sierra 160TMK - are practically unobtanium. It's usually no problem finding 7mm S168MKs, and I've shot quite a few of them in this rifle, with good accuracy at 600yds. It's too heavy a rifle for hunting, weighing in at just over 14lbs with a bipod, but that makes for a very comfortable rifle to shoot extended range sessions, especially when shot with a TBAC Ultra 7 suppressor.

I've thought about building a hunting rifle in this chambering, since I have a Krieger #5 sptr 7mm blank, again in 1-9tw. It's probably overkill for our western Kansas whitetail or mulies , but then again, I've seen some pretty big bucks in a good year when we get adequate rains for good browsing. I would probably use Sierra 140BTSPs, just because I've got a few boxes of them, but there's also Sierra 165 Game Changers that would be better if I wanted to take a longer shot.

I use a similar cartridge. 7 SAW. I use the 162 ELD-M mostly and it works great on everything I’ve shot with it. The 162s will run about 2850 in my rifle and that’s just about perfect from a true short action cartridge.

 

[Bill K]

Can't you just neck down 308 brass to 7mm to solve any brass issues ?

 

[DGP4]

You sure can. You may need to turn the necks, but not usually.

 

[Orr89rocz]

22" barrel chambered for the 7mm-08 will spit out the 120 TTSX at around 3,000 fps which is almost 2,500 lb-ft of muzzle energy and will drift 24" at 500 yards in a 10 mph 90 degree cross wind.

22" 308win shooting 130 TTSX will get you 3,050 fps and almost 2,700 lb-fts at the muzzle and drift 23" at 500 yards in a 10 mph crosswind.

NECK AND NECK...

I have a 7-08 and 308win hunting rifles that are EXACTLY the same in weight etc... I use whichever one I happen to dig out of the safe first.

However.. with the 308win, you can use 110 TTSX that will fly much flatter than the 7mm 120 TTSX.

Another thing I will add.. because both my 7-08rem and 308win rifles are identical, I can NOT tell any difference whatsoever in recoil.

Can also get a 110 in the 7mm. Can drive 3200-3300 fps as well.