7mm TCU vs 7-30 Waters (Carbine)

[jason280]

I'm in the process of building a deer gun for my girlfriend, and I've decided on using one of my Contender frames.  I want to go with a 7mm, but I can't decide whether to use 7-30 or 7mm TCU.  Does the TCU dive up much to the Waters in an 18-20" barrel?  I plan on using 120-130gr bullets, and I'll limit her shots to around 100 yards.

Are there anyy advantages of one over the other?  Brass will be pretty easy to make with either cartridge, so that really isn't the issue.  I've noticed that velocities for the two are pretty close in pistol barrels, but I haven't been able to find any data on carbine length barrels.

Any help will be greatly appreciated!

[Racepres]

Jason FWIW I would rely on the knowledge that like the Herrett's before it, the TCU's were designed specifically for and around a 10" barrel (like the 221 fireball before them). Armed w/ that knowledge and the fact that 7-30's are not a "wildcat" and therefore are more readily available, if it were me I would go w/ the 7-30 and never look back....

[jhalcott]

jason,even in the 14" barrels the 7-30 gains 200 fps on the 7tcu.Both rounds CAN take white tail deer.I have both and for serious deer hunting I generally pick the 7-30.If I get a doe tag or crop damage permit I may take the 7tcu.Crop damage deer are usually taken while I'm ground hog hunting, almost always does and often very close.

[jason280]

My goal is to get a 120gr Nosler BT out to around 25-2600 fps, which should be more than adequate for whitetails here in Georgia.  Would the TCU be a more efficient choice, or should I simply stick with the Waters?  I have die sets for both, so reloading for either one won't be a problem.  

Will recoil be basically the same for either cartridge?

[Gregory]

I just dug out my data from when I had a 16" 7-30 carbine.  120 gr bullet at just over 2500 fps.  Recoil is very mild.  Can't help you with the 7 TCU.

[Pinkerton]

A few years ago my wife decided she wanted to start hunting with me. I traded into a 24" 7mm tcu barrel, and had a stock made up for her. She eventually moved up to something larger but she used that tcu to take a nice little buck (her first) at over 200yrds using hornady 120 SSP over W748, and it's spooky accurate. But I've never chronographed any of the loads.

I've never used the water's in a carbine and doubt the recoil is intolerable, but the 7mm tcu is definately pleasant and mild. You give up some to the water's but not a huge amount and your using about 10-13 grains less powder so the tcu is quit efficient, being so efficient I'm not sure if you gain maybe 150fps or so over a 14" barrel? but it's already doing about 2400fps in the 14" I think the tcu would be a good place to start with your girlfriend.

I hunt prairie dog with a 223 and have traded off to that rifle when the wind kicks up and found it to work great with just a little more holdover using 100gr Sierra HP's, and it's like shooting a 22 hornet with that long barrel, you can shoot and still keep your sight picture through the scope to see the impact.

Like I said before, my wife moved up to a Win 70 270WSM, but still loves to shoot that tcu and calls it her favorite.

[fyrepowrx]

For a while, i had both chamberings in identical 21" factory barrels.

For some reason, i never could get around to doing much with the 7x30, its a fine & great round, but the TCU always seemed to do what i wanted with less blast, less recoil, and less wasted powder. Of course i shoot small deer at about 100 yards, and the TCU worked fine. i guess if you are shooting longer ranges or bigger deer the 7x30 makes more sense.

I  also like the 120 grainers like Pinkerton mentioned in my 21", and it is much more accurate than a 5 1/2# carbine is supposed to be. For a couple of years i didnt have a 7 TCU, since it made more sense on paper to use the 7x30 that did everything it did plus a bit more, but i just didnt use the 7x30 when i had it...several months ago i got another 7 TCU, and i sold the 7x30 barrel this week. My low-recoil loads for the 7 TCU consists of the Hornady 120 SSP over 17.5 grains of H4227...that powder is a bit fast, and so does not get the max velocity you could get with slower powders, but with a charge weight that light, recoil & blast is very light.

Of couse, since you handload you could just get the 7x30 and load it down if recoil/blast is too much for her to use with factory loads...

[jhalcott]

jason the7tc/u will kill deer using 120 Sierra's and a 14" barrel at over 150 yards! I have a 21" carbine barrel that I haven't yet got to use on a deer.I NEVER got 2600 fps from it with any load,did get 2450 though!
  Any way ,you don't need speed as much as accuracy.I have killed deer in Md.with the 10 ,and 14" 7tc/u.Distances were measured from 20 feet to 150+ yards. My 12 year old niece shot ground hogs at 150 yards with the carbine ,and she's small for her age.(had to cut a stock down to fit her)
  Hope this helps,and tell her "good luck"

[jason280]

Thanks a lot for the info.  I'm leaning towards the 7mm TCU, but I'm still considering the 7-30.  I guess it really depends on which barrel I come across first!  

Anyone have some good load recommendations for either?

[steveatsatx]

I don't have a TCU so I can't comment on that, but I have a 14" 7-30 Waters, a 14" 7-30 JDJ and a 19" 7mm JDJ.  My best load for the Waters is 33.5gr of H335 behind a Hornady 120 BT #22810. I know it's a V-Max bullet, but it is the same as the #22811 SSPB it replaced. The thinner jacket gives you the expansion you want out of the Contender. I have 5 clean kills at 85 to 145 yards to prove it. The 33.5 grains is leaning toward the hotter end of things, but as long as my eyes cooperate, I can get 7/8" five shot groups at 100.

satxsteve