338/416 Imp on Rem 700 or 721

[krlemas]

I have always been kind of hesitant to build this caliber on a Rem 700 action because of action strength concern.I have noticed that several members on this site have 338LM built on these actions.I also understand that Remington is now offering the 700 in 338LM.I have a few 700 & 721 actions all CM, reamer,headspace gauge, and 416 brass.I also plan on using the action as a single shot with 32" barrel.Any owners or builders of this caliber or the 338LM please let me know what you think. Thank You

Ken

 

[J E Custom]

The reason the Remington is not recomended for the larger case head
.600+is not because of strength but because you have to open the bolt
face up and this removes most of the boltface shroud.

I use the MK 5 Weatherby action for the big cases(case heads larger
than .534)

Not to blow my own horn but I designed a 416 based on a 375 RUM
that will fit the magnum bolt face(.534 with out any modifications
to the action and brass is readily available at 1/3 the cost of the Rigby
brass.

It was built on a 700 rem long action with no change to the magazine
or the action. (the idea was to build a dangerous game rifle that was
with in range of the average hunter (under $3'000 as opposed to $7 or
$8.000,oo dollars.

It is called the 416 BUFF and is capable of pushing a 400gr bullet
over 200ft/sec faster than a 416 Remingtion mag, so far i'm at
2670 and no real pressure signs.And all loads tested to date have
shot under 1/2 MOA.

My 350gr loads are above 2700ft/sec and shoot nice (50.8 ft/lbs
of recoil).

Just my 2 cents worth
J E CUSTOM

 

[krlemas]

JE Custom

Thanks for the feedback I wonder what remington is using for the 338LM?
I think your 416 buff sounds really good.

Ken

 

[James Jones]

Ibelieve that the biggest torubles with chambering the Rem action in the realy big case heads is like J E said the bolt nose diameter , onceits opened up that far their leave little room for a decient extractor setup. It can be done and their are alot of 338 Lapua's out their as well as 378Wby cased rifles built on Rem 700 actions. Are thier better choices , yea but if you have a Rem 700 laying around it will work. If I were going to bui,ld one I would ceratanly only build on a CM action and I'd have my barrel made so that its 1.35" at the shank rather than 1.25" , probably not needed but I'll pay a bit more for extra insurance.

 

[krlemas]

James

Thank you for the feedback, I ordered my barrel with the 1.35 shank and am planning on installing the Sako or M16 extractor. probably the M16 because of being held by pin.I might also install this in alum. barrel block.Thanks again.

Ken

 

[JayIdaho]

North Idaho?

I've lived in N. ID for a number of years and know of several 338-416 Rigbys built on 700s. All of them are single shots have 30" or longer Lilja barrels and most use custom dies from Hornady. All of the 700s have Sako style extractors but others have been built on Weatherby MkV, Sako TRGS, and Geske actions. All were single shots. Some have taken elk at 990 yards using the 300 gr. Sierra MK.
Some are barrel blocked, some weigh under 16#, some weigh over 65#.
Contact me if you want to talk offline.

1000yds@gmail((dot))com

 

[daveosok]

A great action a lot of folks don't talk about is Armalite's AR series actions. The action is a bit spendy as custom actions can be had for about the same price around 1100 for the action from Armalite.

The AR 30 in 338 LM is a flat base much like a Winchester only its been opened up to accept the 408 case in the past so thats around .640 dia. I think the bolt dia of the Armalite is .750 (some1 correct me if I'm wrong) so you have plenty of stock left over to retain the structural integrity. The ejection port most also be opened up and is safe to do so according to the email I received a while back.

 

[krlemas]

Thank You

Thank you all for the feed back I am going ahead with the build as soon as my barrel arrives just need to select stock now.

Ken

 

[NesikaChad]

338 Lapua and 338 Lapu Ackley Improved. . .

For what its worth:

I have built a few 300 RUMs, 300-338 Lapua Magnums, 338 Lapua Magnums, and 338 Lapua Magnum AI's. I've done this on a variety of actions to include Remington Long actions. I've not experienced any trouble what so ever. I've pushed some of these to ridiculous velocity also.

The way I look at it is this:

If you are relying on the thin margin of material on the bolt to some how prevent the case from rupturing (or containing a rupture), you are only fooling yourself. By this line of thinking, a lot of other actions would be disqualified. We can sit and rattle off names all day of companies chambering guns in this caliber with no ill effects.

If the gun is headspaced properly and if bolt to breech face clearance is kept conservative, experience has shown me that the good ol generic 700 Rem will run all day. A Sako extractor will fit and it will work.

I think the problems and horror stories associated with this is when folks start wild catting the big cartridges to make magnum calibers.

The 416 is not a high pressure case. The 338 Lapua Magnum's bloodline traces back to the 408 Jeffreys. The relation ends there though. The brass is thicker and harder on the Lapua cartridge. This allows for the elevated pressures. 60,000 CUP if I'm not mistaken. A 416 will do that for awhile. . .

I realize lots of people fiddle and fuss with hot rodding 416 cases. All I am saying is that you are running on borrowed time. The case was never intended to operate at that performance level and if/when it does let go on you, all bets are off and I hope you have an ER close by cause you'll probably need it.

Good luck.