7mm Practical

[cowboy717]

Hey guys, I've stumbled across some info on this wildcat and was wondering if anyone has any real world experience with it? Its a 300 win mad necked to 7mm with a 30 degree shoulder. Looks very intriguing to me. I've been in the mindset to build another 7mm.
Anyone heard of it? Good-bad? From what I've read looks perfect for 168s-180s and not as 'boring' (dare I say) as the 7mm RM.
Thanks guys!

 

[Long Time Long Ranger]

The 7mm STW is a standard cartridges and better cartridge. It outperforms the 7mm-300 win mag so what is the point. I have shot both the 7mm-300 wby and the 7mm-8mm rem mag since the 70's along with the 7mm wby and remington and a bunch others. I know these pretty well. When the necked 8mm rem mag case was called an STW in the late 90's and I could get cheap factory brass for it I went with it over the 7mm-300 wby. You can get about the same peformance as the 7mm-300 win mag out of the 7mm Weatherby and the factory 7mm STW is better than both so why go to all the trouble with the 7mm-300 win mag. The short Dakota gives great performance on a standard magnum action with the ability to seat the bullets out more than you will be able to with the 300 winchester necked. When Devin gets his 7mm SIN out there with more powder than the 7mm STW on that short dakota case it will be a good one.

I had to edit because I was in a hurry and had one cartridge on my mind and typing another. I am trying to understand the purpose of the 7mm-300 win mag when so many duplicate it or are just slower or faster and factory rounds.

 

[moombaskier]

I was going to go that route myself, but ended up with the 7LRM...7mm-375 Ruger. I am getting an honest 3170fps with the Berger 180VLD using 73.9grs of H1000 and a Fed. 215m. Here are some pics of the rifle and targets. Sorry no 73.9 targets yet, but they are coming soon. Based on what the 7mm STW uses for powder, I don't see it as a winner. All targets shot at 200yds and the 73.3 loads going 3155fps.

 

[CHARLIEDUECE65]

How about the 284 JAZZ (improved 300 or 338 norma cases necked down). How does this wildcat compare with the dakota round? Haven't heard much of this round lately.

 

[cowboy717]

Well I have heard a lot of good things on the 7 dakota. I'm just wanting something that will shoot the heavys. I have a 7 SAUM that's a tack driver with 130 matchkings and I'm just wanting something that will be fun to shoot and not burn out barrels. I loaded for a buddies 7 RUM that shot extremely well but was toast at 700 rounds. I like to shoot, and I'm horrible at not 'babying' rifles.

 

[Long Time Long Ranger]

I have tested 7mm's quite a bit since the 70's and the 7mm STW is about where the line is drawn for performance vs. any kind of barrel life. Back in late 98 when I first started necking the soon to be released 300 RUM case I did two 7mm's that gave great performance but barrel life was short. I went back and settled on the STW as the top 7mm. I have six of those now and it is a fun cartridge to shoot. Any more in a 7mm and barrel life starts to suffer pretty bad. Some of the new cases mentioned on here like the Ruger I have not worked with since they came along after I retired and quit building rifles.

The 7mm-300 winchester has been done since the 300 winchester first came out. It never gained much popularity because it splits a small gap in performance between the 7mm remington/7mm Weatherby and the 7mm-300 wby and 7mm stw. If a guy wants a repeater with the long heavy bullets he does the remington or the weatherby. If he wants top performance he does the stw or necked 300 wby. The 7mm-300 winchester gives you the worst of both worlds. Less room to seat long bullets out with very little velocity gain over the remington or 7mm wby. It does not have the velocity/power of the STW or 7mm-300 wby. So it sits between there not allowing long bullets seated out and not getting the top velocity. That is why it never took off.

 

[cowboy717]

That's why I love this site, guys more knowledgeable than I am. I understand now. Thank you a bunch. I guess I will go back to the drawing board. As of now I have two Rem 700s in 7 RM. Both I got pretty cheap because the barrels are in rough shape. One is set aside for my Edge build. The other I'm wanting to build another 7mm or 6.5mm. Again thank you guys a lot.

 

[sinarms]

If it were me I would go with the 7mm stw, 7mm Dakota, or when I get the 7mm Sin done I would go with that. It's hard to beat the Dakota brass.

 

[Long Time Long Ranger]

Since you mentioned 6.5 I did a 6.5-300 wsm 2-3 years ago and it was an excellent shooter. It shot so good a guy offered me to much money for it to make since keeping it. Like I said when I had my shop many of the new cases were not out then. Right now if I were looking at doing a 7mm I would look at doing a cartridge with no belt like the Dakota or improved Dakota like the SIN. I have not worked with the 375 Ruger case and don't know about that one. But if you have to neck from 375 down to 7mm I would go with something off the Dakota. Just to much trouble necking that far.

Back when I did all my 7mm-300 wby's and what is now called 7mm STW's we did not have the short fat cases to work with. The improved Dakota can give you STW or better performance in a short cartridge that will feed well through a standard magnum action with heavy high BC VLD type bullets. I shoot the 257, 6.5 and 7mm STW regularly and love these cartridges. However with heavy long bullets they are single shots with the long belted case. The 6.5 STW is a screamer and one of the best long range deer/antelope rifles I have ever owned shooting a 140 grain .612 bc bullet over 3400 fps out of a 28" barrel.

 

[bigngreen]

Here's a good link to some info, the 7mm-300's I've seen and shooters I know who have them like them a great deal. http://www.longrangehunting.com/forums/f19/anyone-own-7mm-300-win-mag-51404/

 

[Rocky Mountain]

I have to agree with LTLR the Dakota improved in 7mm is a good choice but its base diamater of .545 is a pain thats why I like the 7LRM no mag or bolt face changing and it fits into a Rem 700 LA with out having to shortin the throat like a 7mmSTW. I believe that a 7mm 180 VLD at 3000-3100fps is easier to get shooting well and keep shooting well than a bullet going to fastlightbulb

 

[Long Time Long Ranger]

Rocky mountain, Do you have to neck the 375 ruger to 7mm or is that case available in a smaller caliber?

Bigngreen, It is not that the 7mm-300 win mag is a bad cartridge. It will shoot just fine and anyone who has one will enjoy it. There are just to many better choices around that make a lot more sense. That is why it never caught on in 50 years of trying. The 7mm-300 Weatherby got very popular for a while and set some 1000 yard world records but when remington came out with the 8mm rem mag the 7mm-300 wby faltered because of the cheap remington brass and the STW gained extreme popularity. Both of these outperform the 7mm-300 winchester with heavy high bc long range bullets so necking the 300 winchester just never made much sense.

 

[Broz]

Here's a good link to some info, the 7mm-300's I've seen and shooters I know who have them like them a great deal. http://www.longrangehunting.com/forums/f19/anyone-own-7mm-300-win-mag-51404/

My opinion on the 7mm-300 win. is quite high. I choose it over the STW or larger cases for barrel life, and quality RWS brass. I have spent quite a bit of time with the one in the thread BnG linked and it has been shot over 700 rounds now. I like it so much I am building a second one for another friend. Plus I have an extra barrel stuck back with one for myself. I know Youngs Gun Smithing is building a few for customers also. Loading 180's in the factory mag box is very possible and loading them long in a Wyatt mag box or Seeking DBM is a good option too. I feel this round is the perfect case capacity for 180's, and 3200 feet per sec. is pretty easy to get with good brass. Pretty balanced caliber and the accuracy of the ones I have seen is 1/2 moa to way way out there. I would give her a second look before counting it out.

Jeff

 

[Rocky Mountain]

Broz the 7mm 300 Win can be a good option, at the end of the day the three 7mms in question (7LRM,7mm Dakota, 7mm300win) give about the same performance, which one you choose depends on what suits you best, for me the 7LRM tick all my boxes.