Custom 7 mm - 300 Win Mag by Moon at Crescent Customs - AI AX Chassis 

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Michael Forester Not really the, Mashburn was based on the 300-H H case. But yes the same intention.

Greg Quick I thought he built a reg. 7-mm 300 mag. If he built a Practical thats a whole different story. I have talked with Nathan and am building his Practical. He i one smart man and a heck of a shooter. I dream of shooting like him. Go to his web site. He is the man.

Gunslinger no he's the one that did all the development on the practical. He states himself he's not the one to invent the 7mm wildcat but as far as the practical itself he developed. The 30 degree shoulder and the free bore dimensions are of his design. Check out his books. They go much further into detail about load development and cartridge research on the practical. The best wildcat cartridges if not the best hunting cartridge in my opinion.

He recently revised the reamer again through Manson reamers and changed the free bore dimensions so you can start throwing 195 grain bergers. But if you want to stay between 162-180 grain bullets your ptg reamer will work fine.

Greg Quick You are right, I knew that. Going to get one of his books now. Great guy, smart. Good talking to you. Somebody that's informed.

Gunslinger no problem. Glad to hear other people getting involved with the 7mm practical. It's like that lost unicorn that not a whole of people know about but it's getting some steam. Good talking to you. Good luck with your project.

I have a 22 Nosler AR. Ammo can be a pain sometimes but I love it! Long range and "mac set your hair on fire."

+madcow3007 dropped right in.

The idea behind it is to be a happy medium between the Rem mag and the ultra mag. better speed but not sacrificing barrel life. It's not intended to be an end all be all. Here is some of the background behind it. - www.ballisticstudies.com/Knowledgebase/7mm+Practical.html

Long Range Shooters of Utah Yes, I read that article earlier this year but dismissed it as largely hype. First of all, the loads it gives using H1000 powder for 3 bullet weights must be absurdlly high.79.5 grains of H1000 for 160 grain to168 grain bullets? C'mon, those loads exceed 7MM STW loads which uses a full length 2.850" magnum case instead of the shortened 300 Win Mag's 2.620" case. And the SAMMI leade is almost as much at .192" as the 7MM Practical Magnum's .204". So if you think you're going to get much more barrel life with those loads and high pressures, you'll be disappointed. And besides, you'll ruin the brass after as little as one shot by expanding the primer pockets. I know, I've ruined hundreds myself in the quest for greater velocities. It gets expensive, especially with Norma and Weatherby brass As I said, the case has about 4.5% more volume than the 7MM Rem Mag, so at best, you'd get that much more energy for a given barrel length. That translates into about to about 75 to 100 fps for a 160 grain bullet. Heck, the performance figures quoted for the cartridge exceed those of a regular 300 Win Mag. Think about it: When you neck a cartridge down from .308 to .284, the energy must go down, not up. Which is why a 264 Win Mag has less energy than a 338 Win Mag which, in turn, has less energy than a 458 Win Mag though they all have the same parent case. If I wanted an extra 100 fps second, I would have tried using Norma cases in 300 Winchester brass. They generally weigh about 20 to 30 grains less than American brass and are thus good for about 2 to 3 grains more powder. I was able to get an extra 50 or 60 extra out of my 375 H&H with 300 grain bullets using reformed Norma brass though that varied with bullet selection. Or why not keep life simple and go with the 7 MM Weatherby Magnum if you need 3200 fps from a 160 grain bullet? Yes, it has .378 of freebore, but my 270 Weatherby, which uses the same parent case and freebore with a Shilen barrel, was able to average .6 moa with 150 grain hunting bullets. I had a whole slew of rifles in various 375 calibers. You'd think the .3/4" freebore on a 378 Weatherby would make it less accurate than 375's without much leade; however, they displayed the same or better accuracy than calibers with custom match grade barrels and little freebore. Whether it was a 375 H&H, JRS or RUM. Go figure. Another confusing thing are the complaints about the stock Remington Model 700 long action magazine being too short. They may feed like crap - or not even feed at all, as with my 300 RUM - but too short, they are not. I just measured one at 3.701" Plenty of room for even long bullets. I also dislike videos bragging about shots on game at a gazillion yards to demonstrate a cartridge's supposed prowess as well as that of the shooter. I have to wonder, given the impossibility of gauging the wind "way out there" and the fact that even military snipers miss a lot more than they hit at ultra long ranges, PLUS the fact that you need to set up the point of impact for EACH application, I wonder if at least 10 game animals are either missed or needlessly wounded for every RU-vid video showing a successful hit.

no it was a 7-300 reamer. Yes it's held up far better than expected. I'm at more than 2000 rounds and it still shoots great.

I've only put about 1000 rounds and it's still shooting 1/4" groups. I expect maybe 1500 out of it at best.

+seanw158 I definitely like the 7mm better than 30 cal because you can get the same or better BC from a smaller bullet. A 180 gr Berger Hybrid blows the 180 gr .30 cals out of the water. So yes I would definitely choose the 7mm over a 30 cal all day long unless I'm headed to Alaska to hunt kodiak or moose etc. But even then with the new Berger 195's...hmm. I dunno. As far as the 7-300 I wouldn't recommend it to a newer reloader as any wildcat, even an relatively easy one to create like this brings with it some challenges and uncertainties. The caliber is amazing though. I have two of three peers that are running a 7 practical which is nearly identical and they are pushing the new 195 bergers over 3100 FPS with reloader 33. That's some incredible performance when you consider the BC of that bullet. The 195 has a 5% higher BC than the 230 gr VLD!!! That's nuts. Cartidge wise the downside to the 7-300 is that the case is belted so brass life is shorter than none belted cases like the 7 saum or 7 wsm. Pluse both of those are short actions which is nice. You can also run them in a long action too though. At the time both of those were nearly impossible to find brass for and I had tons of 300 win brass so that made the decision for me. If you're looking for a heavy magnum, don't care about weight, brass, etc you just want to really push it to the max and reach out a long long way without jumping to a 338 then the 7-300, 7 practical or 28 nosler are awesome. If you are more of a tactical shooter, or need less weight, want a little more barrel life and can find the 7 wsm or 7 saum brass then I'd go that route. Check out my buddy's video shooting his 7 WSM at 2000 yards at a 24 x 30" plate. It will blow you away how high his hit to miss ration is at that distance. Just search 7 WSM at 2000 yards. His channel is StainlessTumblingMedia.

+seanw158 Check out ES Tactical or Crescent Customs. ES Tactical will be slightly less expensive and a faster turn around if you're looking to rebarrel your current rig. Tell them I sent you and they will take great care of you. Both are huge 7mm fan boys and have built many 7-300's and practicals. Eric of ES tactical is a 2 time palma national champion 13-14'

+Long Range Shooters of Utah Wow, Thank you for all the info! You defiantly gave me a lot more to consider with the cartridge. As I am an avid reloader, this would be my first wildcat but there appears to be some good specs and instruction on how to neck the 300 case down. It sounds like the 195 bergers(which seem to be plentiful) would be the route I take if I do take this road. I was looking into the 7 saum, it looks like a wicked round but I just finished a 6.5 Creedmoor build so i figure I'd dive into the long action this go around. I'm defiantly leaning towards the 7mm though! I'll get in touch with these guys you listed here pretty soon and see what other wisdom they can give me as well as the price! Thanks again, I will have to let you know what the final outcome is on this rifle. And I'll have to take a drive from AZ up to Utah to liberate some water from a milk jug.

We'd love to have you come up and shoot with us. If you're a seasoned reloader than it's just a matter of running a 300 win mag die, start round one with a .315 bushing then again with a .311 typically. That's it.

www.ballisticstudies.com/Knowledgebase/7mm+Practical.html

The 7mm Remington Magnum is based off the 375 H&H, no the 300 Win Mag.

TwisTed Taipan I thought the 7-mm mag was built off the 338 win. Mag. ?

"The 7mm Remington Magnum rifle cartridge was introduced as a commercially available round in 1962,[2] along with the new Remington Model 700 bolt-action rifle. It is a member of the belted magnum family that is directly derived from the venerable .375 H&H Magnum."

TwisTed Taipan Thank you ,the HandH is a daddy to a lot of them lol . I owned the 375 , great gun, great killer.

You can always rebarrel it in another caliber but it's not a quick change like you would get with the AI AX rifle or the Desert Tech PRS.

And how many rounds you getting threw the barrel before is burned out? Around 1500 rounds?

It’s a 338 cip Chassis & mags. My barrel went over 2000 round because I ran a pretty mild load.

Shooting out to 2200 yards would you still go with the 7mm/300 or 7 saum?

Joshua Greer I’ve done 2650 with my 6.5 x 47. Check out the video. Hit a 24” plate 4 times out of 10 from cold bore. The 7x300 is far more capable

Joshua Greer it’s not just a 338 but a 338 CIP which is even longer.

We have several videos shooting 100 yard groups as well as long range groups out to 1 mile.

Thx I'll chk em out

It's 18lbs with the scope (Nightforce ATACR & Nightforce 6 bolt rings) so I would estimate 15-16lbs. It's hefty with that chassis, 28" #7 contour bartlein barrel and defiance deviant action. Doesn't kick at all though.

28" but the most common length is 26"

I just watched another where it said 28" how do you like 7mm-300, I am currently looking at building a custom 338 Lapua,... like you I love the 300WM but wanting to reach extreme ranges of 2500+.... what's the furthest you've shot?

2240 yards. If you want to reach 2500 I would recommend a 338 Edge or Lapua.

Hornady recently came out with a new 225gr .30 caliber ELD bullet with a .777 BC. Someone worked up a 300 Win Mag load and ended up getting sub moa groups @ 2900fps. Personally I'd much rather run that than a 7mm-300, due to ammo availability and energy downrange. I compared that load to a factory Hornady 338 Lapua load and it beats it in every aspect besides 300lbs less energy @ 1000 yards. I think I can live with 5.56 muzzle energy at 1000 yards though...

About to get one in 7mm rem mag, but still standing under choose between Tikka T3 or Remington Sendero, what you can recommend. I'm not from US. ALSO PLANING TO CHANGE STOCK FOR THE CHASSIS

If I had them I absolutely would. My borrowed the reamer from a buddy. He's the owner of Stainless Tumbling Media. You could reach out to him and see if he has the specs. I know he had the reamer made by Pacific Gauge and Tool. they may have the specs on file. Sorry I can't help more.

+Jim 1234678910 No I haven't

+Thomas Delacroix yes I did.

What had to be done if you don't mind?

Also, shot in the dark, where would you go to sell a used chassis? I have a AICS AX 2014 model in 300WM that I am going to sell.

Armslist, gunbroker, gun show, ebay if they'll let you, reputable forums.

+Joe Dirt Yes I still have it. I believe the rings are high rings.

Are you planning to reload ammo or just buy factory ammo?

Long Range Shooters of Utah mostly factory but. Maybe down the road but notnin the short term plans yet.

ajfam871 You'll find that the majority of LR shooters reload as a way to develop a custom load for a particular rifle and save $ since you'll likely be shooting more often. I would recommend going with a .308 or a 6.5 creedmoor as there is high quality factory LR ammo readily available. Federal Gold Medal Match .308 and Hornady 6.5 creedmoor are both excellent and not terribly costly. $20-25 per box of 20. I agree with your comments about the 300 win mag. It's a superior round to the other but packs one hell of a wallup in the recoil department and can create bad habits. I would go with somehting lighter like the .308 or if you want the performance and ballistics of a 300 win mag in a lighter platform don't overlook the .243 or 6.5 Creedmoor. The majority of competitive tactical shooter will chose either a 6 or 6.5 for long range. Your drop on a standard 243 is actually better than a 300 win mag at the same distance. But if you're going to be using factory ammo then go with the .308 or 6.5 creedmoor. Visit accurateshooter.com and do some reading on all the calibers on the left side. It might surprise you.

ajfam871 zaa

Pelican 1750 and I cut the foam myself with a hot wire cutter I bought at Hobby Lobby for $20. You can use an electric knife too. You can also buy the case without foam and get harder foam that's easier to cut and is preferred over the soft stuff. You can also get these with pick-n-pull foam as well. tinyurl.com/ydffmj9a

Long Range Shooters of Utah, LLC I was wondering how the cuts look so good thanks bud

Yes, in order to have a magazine that is long enough for a 180 berger hybrid seated in a modified 300 win mag case I had to go with the 338 CIP. That was the most challenging part of building this rifle was figuring out what mags I would have to use and what chassis. Ultimately after tons of research, phone calls etc the 338 CIP was the answer. I just had to bend the mag lips inwards to hold down the small 300 win mag case instead of the 338 Lapua case it was intended for. Works great.

Long Range Shooters of Utah Bryce..Love the videos and this set up of your rifle. Please post a video of you reloading this cartridge. Would really appreciate it. thanks

soon

+skelleytim Redding full length 300 win Mag die with multiple bushings. I size the neck down in 2-3 steps that's it.

Long Range Shooters of Utah, LLC what about the bullet seating die?

TriumphAthletics 3150 FPS

I'm not sure what it was before I mounted the scope etc but with my Nightforce ATACR and harris bipod it's about 18 lbs unloaded.

Justin Eplin 1750

Nice rig for sure, how did you get such a great cut on the pelican ? Recently I attempted one and it didn't come out that nice.

+miguel contreras 28" Bartlein 1:8.75 twist #7 contour

I can push a berger 180 hybrid at 3150 fps if I want. I had a ton of 300 wm brass and my buddy had just built an amazing 7-300 so I went with it. 7 Rem Mag would be a simpler choice. I'd go 7 SAUM or & WSM first though.

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7mm...I can tell by the "re" at the end of millimeter that you're very possible from outside the US. Within the US it's very common for people to refer to the 7 milimetre as you call it as a 7-M-M. Sorry but it's true brother. That's all anyone ever called it growing up so it's a habit.

Even the spell check on my computer picked up on millimetre as a mispelling by US standards. I'm sure in Canada and elsewhere that's exactly how it's spelled but not here.

its metre not meter.

Jason Moyle gotta love the 7mm round eh?

dipshit.

+Patton243 Except when you're pushing 195's at 3100 FPS but who would want to do that right.

Whatever floats your boat, dude. If this gun makes you happy so be it. I personally believe it's not a very efficient cartridge, and I think it's pointless to build something like this when you can shoot other commercialized calibers on the market that are a lot cheaper. Furthermore, if your'e shooting 195s your barrel life wont be very good.The 7 mag is overbore; this thing is even worse.I can go anywhere and buy reloading stuff for a 7mm mag or any of the common .30s on the market. You can't. Enough said.

Patton243 If you're trying to make the argument that a 7 rem mag or 300 win mag are easier to find factory ammo for than you're correct. And yes it's overbored. The video isn't about the most efficient, cheapest to shoot, longest barrel life option out there. If it were we'd be talking about a .308. This and no other caliber is the end all be all perfect fit for everything. If you want to a ridiculous flat shooting extreme long range rig without jumping to a 338 edge then the 7 mm Practical is solid. Is it the end all be all...no. But when 7 WSM and 7 Saum brass were tough as hell to find and I had a ton of 300 WM brass and H1000 it was a perfect fit and I wanted to try something a little different. PS - pushing 195's at 3100 is incredible and clearly this rifle is not built for best barrel life.

Patton243 www.ballisticstudies.com/Knowledgebase/7mm+Practical.html

Long Range Shooters of Utah Pretty much everything you said was recited in your first response. Unless you have unlimited income and money isn't an issue then something like this is fine, However, most people are on some type of budget so I think it's a poor decision to build something like this. If this is something you made to be "different," then I think you made a poor choice and will end up wasting more money in the future on this platform. Reloading for this cartridge is going to be expensive. A 300 win mag case doesn't last as long as say a 300 WSM case and has a belt for your head space which causes issues in some cases. I can go on about the reloading apsect, but I won't.. Good luck with your rifle and may you replace your barrel every 700-800 shots because that's what will happen. Unless of course you don't care about accuracy. Have a nice day.