Home Forums Hunting & Shooting Gunsmithing Rechambering 7RM to 7STW...is it worth it?

I have a Rem 700 7mm Rem Mag that I am thinking of rechambering to 7mm STW. I wanted an STW when I bought the gun but could not find any in my price range. I also considered the .300 Win and I finally decided since I will likely shoot more Whitetails, Muleys, and Antelope than Elk I would go with the 7mm Rem and possibly buy a .338 Win for a specialized Elk gun later.

At any rate, my 7RM shoots very well with pet loads, best ever was a .716" 200 yard group running 140 TTSX's at 3250 out of a 26" barrel.

I am switching to 150's and would like to maybe go to 160s and thought about punching the gun's chamber out to 7mm STW which was the object of my desire.

I would like opinions on whether it is worth it to do so. I reload so finding ammo is not an issue.
Would I chance losing accuracy doing the rechamber? Relative cost of a rechamber?

Obviously the 7STW pushes bullets a couple hundred fps faster than the RM does. I would have went with a .300 Win but I got caught up in ballistic gack. Further gack is pushing me to the STW. Thoughts?

Accuracy wise there is risk involved anytime you rechamber. Your rifle seems to be performing remarkably well for a stock 7mm Rem Mag. Were it mine I would leave it like it is. Maybe save the STW for down the road when you rebarrel.

I don't see any reason to re-chamber. If a 7mmRM isn't getting the job done a faster 7mm isn't the answer. I'm a big fan of the 7mm 140gr at 3200fps and 160-170gr at 2800-2900fps.

If you want a 7STW,why not just buy another rifle and keep your good shooting 7mag.I have both,they are both good shooters.Both are capable of killing game farther than I can accurately shoot.I have decided to use the 7mag for lighter bullets and the 7STW for the heavyweights.Yes,the 7STW will out perform the 7mag,but it does come at a greater cost.You will use about ten more grains of powder,mine is much harder on brass than my 7mag,brass can be hard to find at times,there is a little more recoil,about like the 300 Win Mag,which also uses about ten more grains of powder than the 7mag also.It only hurts for a little while when you have too many guns.I'd rather spend my money on them than a bunch of crap,at least you'll have something to show for it and you can always sell them or trade them.

Depends on your "needs" and "wants". Like everyone else has said, pretty much your current 7 mag will do about anything you want it to. But on the flip side, if you want a 7 stw then go ahead and ream it! I was a 7 stw junkie and had several factory bbl's rechamber to stw with really good results ( as long as I stuck with a remington, Browning a-bolt was only one that wouldn't shoot well). I've had a coulple that were honest 1/2" guns afterward and none worse than 3/4". As far a cost, I've had it done for as little as $60 and as much as $125. I'm now an ackley nut, so take my advise for what it's worth. Just my 2 cents, when in doubt... ream it out!

Takem,

A few years ago, my buddy was in a conversation with the Remington Custom Shop. (He wanted some questions answered concerning the ordering of a new 40-X) One of the questions that came up was the value of a 7MM STW and 7mmRUM, vs the 7mm Rem Mag in terms of velocity... The man at the CS told him, if one is not running at least a 26" barrel, then he is wasting his time.... And a 28" is even better... !

Long way of saying that I don't think it's worth it. I've owned 3 7mm STW's... and at the moment, the only 7mm Mag I own is a Rem. 40-X. I'll likely never own another 7mm STW.

That said, I've scratched my itch... Perhaps you have yet to scratch yours... The only one you have to please is yourself...

GH

Takem,

YES, YES and YES, do it. You will not regret it. It is worth it. Take it from someone who has done it and is doing it again.


Rem 700 7mm mag barrels are cheap and a dime a dozen I just bought two this past week to punch to STW. An easy and cheap conversion and replacement.

I can't tell any difference in recoil between the 7 rem mag (of which I've owned 3 in the past) and the STW.



The above quote is pure and total horse crap. The guy who said this is clueless.
I plan on going STW with a 24" as well.
It's still worth it.

I strongly doubt you will lose accuracy and I'll bet you gain there. The STW is not finicky with pressure spikes like the 7 rem mag will give you. And I've found it to be an extremely accurate cartridge that is very easy to load for and get top speeds without having to push or lean on it hard like the 7mm rem mag.

One and only thing with the STW. You will need a Wyatts box to seat VLD bullets, and that is inexpensive.

I can't say enough on how much more cartridge the STW is over the 7 rem mag.
It truly is worth the conversion.

The ballistics gack is real with the STW.

I hope its worth it ! - i am getting my 1965 Rem M700 7mm rem mag with a factory stainless steel blued barrel rechambered to 7mm stw now ! i hope to pickup around 150 fps with 140-160 gr bullets ? i guess we will see - Cheers Jim

Let us know how it works out with the chronograph, and let us know what another 150 fps does with the drop tables at 500 yds.

I have rechambered several 700 Remingtons in 7 RM to 7 STW. They all shot accurately and gave good velocities. Also there is no alteration needed to make them feed. It is a good conversion for the handloader.

Shooting 120 TTSX's at 3,850 with RL22.

That's flat.

I run a 26 inch barrel on my 7 RM anyway.
Basically to get what I want out of the 7mm Rem I am running at absolute max powder charges for bullet weight. Using a WLR primer and 69.5 RL 22 gets me to 3250 with 140s which is a consistant 1/2 inch load. I tried 66gr and a mag primer but accuracy suffered. It took a lot of load development to get there but I am not happy with 1MOA which was easy to get. I am a bit of a looney when it comes to this stuff.

I plan to switch to Retumbo with 150 TTSX's this year. Im flat out sick of the temp sensitivity I experienced with RL22. zeroing three times from Sept to Nov due to temp swings gets old. I hope I have better luck with Retumbo. I realize now a lot of the issues I had during load development had to do with the temp sensitivity of RL22.

I think the 7STW could get me the speed with heavy bullets I want which is over 3000 for 160s and 2900 for 175s without pushing it as hard. Basically what I am saying is I want .300 Win Mag speeds shooting the high BC heavy 7mm Bullets. I've read data for the 7mm RM in that region but it calls for RL 22 or 25 and after my experience with RL 22 and temp shift Im not going down that road again.

RS Magnum is your huck.

3,200 mv & 175's at 3,100

Very nice group!!! Out of a STW I assume?

I am def going to look into the conversion further. It might not happen this year with funds as they are but something to look forward to.

I always thought the 7 STW was the ideal big 7. I could get where I want velocity wise and then some going that route.

I got a deal on Hornady 7MM .284 DIA 162GR BIG GAME POLY CARB TIP 28452 bullets and moly coated them

Comparing cartridge performance with Quickload and Quicktarget at close to optimum powder choice and 65kpsi:
7mmT/CU ........................26.1 gr H335 2330 fps -471 yards
7-30 Waters ........................30 gr W748 2456 fps -395 yards
7mmBR ...........................31.2 gr W748 2510 fps -360 yards
7mm IHMSA .......................40.2 gr Re17 2704 fps -247 yards
7mm-08 .......................40.6 gr IMR4895 2789 fps -198 yards
7mm-08AckleyImproved .........43.6 gr Re15 2833 fps -171 yards
7x57mm ...........................44.6 gr Re15 2843 fps -165 yards
7x57mmAckleyImproved .........46.4 gr Re15 2873 fps -150 yards
284Win .........................50.0 gr IMR4350 2890 fps -172 yards
280Rem ............................53.5 gr H414 2961 fps -152 yards
7mm Rem short action ultra mag 55.5 gr Re17 3015 fps -73 yards
280RemAckleyImproved ........57 gr IMR4350 3019 fps -71 yards
7mmRemMag ......................68.2 gr Re22 3129 fps -15 yards
7mmRem ultra mag ............83.3 gr IMR7828 3130 fps -15 yards
7mmWeathMag ....................71.8 gr Re22 3170 fps +7 yards
7mmSTW .............82.2 gr Ramshot Magnum 3158 fps 0 yards

I made that chart last year.
Now I only consider Hodgdon extreme powders.
Re17 gives 200 fps over most powders, but has to be reduced and extra 200 fps for temp compensation.
And in reality, I run Mauser case heads at 67 kpsi and H&H case heads at 72 kpsi.