Precision Hunting rig WHAT OVERBORE CALIBER

nevanevan

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I'm trying to get some help for a friend that want to build an extremely light weight, way overbore, laser beam rifle. He doesn't care about throat erosion, barrel life etc and the price range will be about $3000 before scope. I was personally thinking about a 7STW but from a friend helping him reload also I would like to stay away from the belted magnums. Some parts I was thinking for a build would be;

Bell and Carlson Hunter stock
stiller action (length would change depending on caliber)
Shilen or kreiger barrel as I have heard good things
Timney trigger

Let you imaginations run wild and experience would be even better. We are really thinking between a big 7mm to a 338 edge, but he would like to keep the barrel around 24" which might pose a problem with a cartridge like the edge. He currently has a 300WinMag but would like a little big more performance regarding ballistics which explains the inquiry for the 7mm bullets or 338. It would also be fun to try some wildcatting

Thanks in advance,
Evan
 
Here are some rather absurd over-bored magnums:

Ranked reasonable to stupid awesome:

1) Any of the RUM family: 7mm,300,338,375
2) Lazzeroni's: firebird, warbird, titan (note the price and rarity of brass)
3) Allen Magnums: 6.5,270,7mm,338
4) Maybe some variation on the 338LM (good brass)

As for the use of a 24" barrel, maybe it wouldn't be a bad idea to look at the WSM/RSAUM family of cartridges. Though the factory versions may not have the ballistics you are looking for out of the box, you might be able to change it up some and maybe opt for a 6.5WSM. Not the massive heavy hitter you are looking for, but definitely flat!

Personally I run a 300RUM and a 338LM. Both are good, but I like the 300 RUM simply for the selection of bullets (from cheap to ballistically efficient). Plus the RUM is pretty flat and very manageable in regards to recoil without the use of a brake. My 338LM came with a brake factory installed, so I cannot speak to its recoil in an apples to apples sense, but braked and 250gr HPBT works pretty well. The RUM's are always done with 26" barrels, though you could run a 24" with only a little loss in performance.
 
I use a Rem 700 XCR 300 Win Mag with Bell Carlson stock, Timney trigger, 26 in braked barrel. Good out to 1000m with 215 Berger hybrids. Bedding and brake done by ATRS. Comes in at just under $3000 once mods are complete. Rig is quite light and shoots well. Factory triangular fluted barrel. Will probably turn it into a 338 Edge when I've shot out this barrel.
 
My buddy is looking for a cartridge that will "reliably", and "humanily" dispach elk to sheep to about 600yards. Please don't turn this into an ethics point of view, as well I know that a properly positioned 22LR bullet will do the job. This is mainly a fun reloading project that will get some great mountain use as well as some range fun. The 338 Allen magnum looks very interesting, but I bet the brass is the cost of a your right arm. Also looking at the 6.5WSM however it is very similar to a 270WSM which he has so I wouldn't really see the benefit in that caliber. The 338 RUM also seems to fit the bill, as it is beltless and factory ammo could be bought.

Any more input regarding the 338 calibers and barrel length? Is there an absolute requirement to have a heavier barrel with say a caliber like the 338 edge, or could you run a match grade 26" barrel with a pencil profile that would still be accurate as a heavy (assuming you allowed the barrel to cool well between shots)?

Has anybody bought a caliber like this with an aftermarked barrel and used a slightly smaller neck reamer, considering that wildcatting generally involves the need for turning necks anyways. Do tight necked barrels chamber as easily as a SAMMI factory chamber if they are turned properly etc?

Sorry for all the questions but pursuing a custom rifle, alot of considerations must be taken into play that the regular hunter and amateur precision GunNut might not consider.
 
For what it's worth I remember a thread a little while ago where rick from ATRS put together a rifle with a carbon wrapped barrel and a mcmillan ultralight stock. Those guys know their stuff. I say give em a call.
In regards to calibur I think it's mostly personal preference. All the ones listed should do the job.
 
Way light rifle with an overbore chambering - how's he for dealing with recoil?

257 Wby. Will do what you want and not kick you into tomorrow.

7RM - yes, dull and boring but oh so very good with modern loadings. 7 STW is very ineffective in 22 to 24" barrels.

6.5-06 - Easy to make a standard action light and most mags hold 4 rds. Again, recoil will not send you to tomorrow and ballistics are very very good.

Light rifle will also necessitate a shorter barrel so massive chamberings just end up making more noise then speed.

YMMV.

Jerry
 
Has anybody bought a caliber like this with an aftermarked barrel and used a slightly smaller neck reamer, considering that wildcatting generally involves the need for turning necks anyways. Do tight necked barrels chamber as easily as a SAMMI factory chamber if they are turned properly etc?

Of the calibers you've brushed upon, I've have tight necked versions of the 7mm STW and the .338 Edge. There's no doubt in my mind that for a hunting rifle it is a total waste of time and the necks have since been opened up.

I'm interested in what you consider extremely light weight. A Stiller action and B&C Hunter stock would be about 4 1/2 pounds by themselves. Add even a light barrel and scope to that and you're into "standard weights".

I think you should go back to the beginning and start with a clean piece of paper.
 
My vote for Lazzeroni 7.21 (.284) Firebird. You should see that case. My friend has one , and it is impressive. You'll be a superstar at the range.
You won't fire that gun enough to get throat erosion, too expensive ammo wise.

Mush
 
Of the calibers you've brushed upon, I've have tight necked versions of the 7mm STW and the .338 Edge. There's no doubt in my mind that for a hunting rifle it is a total waste of time and the necks have since been opened up.

I'm interested in what you consider extremely light weight. A Stiller action and B&C Hunter stock would be about 4 1/2 pounds by themselves. Add even a light barrel and scope to that and you're into "standard weights".

I think you should go back to the beginning and start with a clean piece of paper.

Good to hear about the case neck issue. Obviously it is a matter of perspective, lightweight for caliber ie, a 6.5lb 308 is great just as a 9.5lb 338 edge would be great. Not saying that there is a maximum weight of 7lbs, but as lightweight as possible given the caliber. As Jerry had mentioned, if the large calibers aren't effective using 24" or shorter barrels then I might be back to recommending one of the calibers he mentioned such as the 7mm Rem Mag. Also, what Bandits had mentioned about the SAUM family sounds interesting as this would be a short action to cut weight down.

Any opinions on barrel contour, pencil vs regular hunting etc?

Again all your opinions are greatly appreciated
 
Get a top quality barrel and contour is less important while still maintaining performance.

I have supplied Shilen match barrels in #2 contour to build exactly what you described. Rifles were 'smith by Guntech in 260Rem. The customers are thrilled with the performance.

Not some super fire breathing monster but they have tagged their targets at will and the animals didn't seem to care.

I believe the finished weight with scope was 6lbs.

Right now, you have conflicting goals. Determine what is most important breaking down every part of the rifle. The parts will sort themselves out pretty quick.

Or you can have a look at the Ruger American. Surprisingly well put together rifle and very light. Spin on a quality pipe and away you go. Tikka T3 lite would fit the bill here too and offer different chambering choices.

Jerry
 
I've got a PGW lightweight sporter built on their Titanium M18Ti action and chambered in 6.5STW. With a 27" Barrel (.610" muzzle) rings/bases and a not particularly light HS Precision Bottom Metal/magazine it weighs 6.8 pounds.
Not surprisingly the barrel is shot out and needs replacement but 142gr. MatchKings at 3420 fps is pretty damn awesome performance!

I would get a Pierce Titanium LA, McMillan Hunters Edge carbon stock, PTG BDL style bottom metal as the foundation for a build and chamber it in either 6.5STW or 7STW. While I would not want to shoot it prone all day, either chambering would not be offensive for its intended purpose without a muzzle brake.
 
Another vote here for the 7 STW, its a great overbore cartridge. You said your first instinct was to go with the STW, but now are shying away from the belted magnum. Personally, I don't mind the belted magnum casings at all. The 7mm STW is a great performer, and is fun to work with. You can load up screaming fast stuff in the 140-150 gr bullet weights, or because of the great 7mm bullet selections, pick out heavier stuff, and still have great velocities. 26" barrel is a must. One thing if you are building a light weight rig, like you suggest, is a lot of these big overbore cartridges are heavy hitters in the recoil department, this will be especially true in a lightweight rifle.
 
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As always, Jerry/Mystic speaks truth and experience.

Me?, my 6.5/06, it shot really really flat, hit hard way out there, and so scary accurate too(1/2 moa) ... for it's entire 1000 rnd. barrel life.
I'd do that one again. Two barrel's chambered at a time.
 
I think we have narrowed it down to a 7mmSAUM. Thanks for everybodys input. Expect an email Jerry as I will be passing on your information to my buddy afterall you have been the guy supplying the parts for my precision 223 build. This CGN community sure is great when it comes to gathering from combined hundreds of years of shooting expierience.

Evan
 
Yes. A goldmine when you need solid info. :)

Let us know how well your Mystic .223 and buddies 7saum work. Range report?.

Once we start building there will be photos and details or it. I realize the 7SAUM is not seriously overbore, but judgeing from what everybody was saying is one of the few cartridges that might work with a short barrel. I guess the initial requirements that I set out on were unrealistic. Afterall, who wouldn't want a 16" pencil barrel 338 edge that shoots to the moon in 1"groups and weights under 5lbs. On a different note my savage 223 barrel im sure will arrive in the soon coming months. Its a shilen 8 twist with the new ratchet rifling. It should be promising with 80grain AMAX. I went with the regular 223 and not the improved simply so that I could always shoot bulk through it should I need to for gopher season. There will be a range report with that one when it arrives as well considering I will be doing my own barrel change and headspacing.
 
Though the 7SAUM has made its bones in the long range target shooting circles, I don't know about the field shooting people. I have heard some reports of issues in regards to feeding, also the availability of brass may be an issue given the demand from the target shooting market (which could also be a plus). For the difference and simple availability, the WSM family is always good. Sure it might not have the neck length of the SAUM but it will do.

I found this article a while ago and it might shed some light on the topic:
http: //www.accurateshooter.com/guns-of-week/gunweek064/
 
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