Coverting 700 BDL 30-06 to 240/6mm

[merbeau]

Hope this is the correct forum – first time posting. Mostly I have been a Bullseye Pistol/Skeet Shooter for years and have mainly collected rifles rather than shoot them. Since moving to an area that provides more opportunity for rifle use (i.e., hunting and competition) my interest in long gun shooting has increased.

During one cold morning while reading one of my reloading magazines I came across a comment that any of the ‘06’ family can be re barreled to the 240 Weatherby, 240 Gibbs, or 240 Hawk without having to extensively modify the bolt or magazine. The Hawk as I understand is based on the 280 case but can be formed from a 30-06 case.

Further reading lead to several articles that the 6mm Norma BR is another option because of it being extremely accurate and provides extended barrel life (which is a consideration of mine), however, it is based on the 308 case which is a short action cartridge. I believe the bolt on the 30-06 would work with a 308 case since it is a shorter 30-06 case. I would assume this would require more work in making sure the bolt locks are locked in place correctly and the head space between the bolt and barrel and cartridge is correct.

Currently I am in the early stages of project planning to convert an older Remington 700 BDL (which was originally configured in 30-06 caliber) custom built to a 240/6mm cartridge. The primary use of this particular configuration is varmint, coyote and some local competitions (300 to 600 yards) preferring to use a 25-06 for larger game (e.g., deer, etc.).

What cartridge would be appropriate to build the custom rifle? Would building a 6mm BR just be adding extensive cost for retooling the bolt and magazine, etc.? While commercially available brass is a preference I do reload ammunition and would not mind forming brass if it is not commercially available.

 

[sharps]

I have done exactly what youre talking about.........30-06 to 6 MM Remington with NO problems at all........Feeding, extraction are non issues but if you think
you are going to take a long action Remington and magazine feed 6 BR's out of it
you're on a long bumpy road!!!! They will jump out of the magazine or nose up
into the top locking lug area as the rails in the action simply wont allow such
a short bearing surface stay on a angle that will get the nose of the bullet into the chamber.............The issue is too much metal is removed to allow the long
fat cartridges to feed and welding the inside rails on a action is a good way of
destroying the action..........You could single shot it as I have done to both of my 6 BR's............that will work fine and everything will function fine, just drop a loaded round on the sloped follower and close the bold.......If you decide to
go the 6MM Remington route I have a good set of dies and a lot of NORMA brass that is unfired for this round....................

 

[merbeau]

Hi Sharps

Thank you for the reply. I kind of thought trying to make the SA 6mm BR work in the LA Rem 700 would have some serious issues and I do not want just a single shot rifle.

I started by looking at shell holders for the 30-06 and obviously the 6mm BR came up along with 6m-06, 6m-284, 240 Weatherby, 240 Gibbs, 6mm Remington and several others.

I was leaning towards the 6mm Remginton because of the commerically available brass and lot of loading data and unless one is shooting at extreme distances it doesn't warrant going to the 6mm Ackley Improved.

What brand are your dies? Or perhaps are they standard size.

 

[bheadboy]

i have had 2 6mm rem and both were good shooter, accurate, easily took white tail and not hard to reload.

However, you comment of 600 yd possible for some shooting, i would suggest you go ahead and look at the
AI version as the added velocity with heavier high BC bullets will be an advantage to you.

feeding would be no problem.

Bob

 

[Trapper243]

I am glad you asked the question, as my wife has a nice McMillan stocked FN Mauser in 30-06 that could probably use a new barrel. Since the 6mm seems to work well, it sounds like necking up a bit to .257 Roberts should not be an issue. In her case we are looking for less recoil and a deer killing alternative to the 30-06.

 

[merbeau]

Hi Trapper
As in my original post the idea came after reading about converting a 30-06 to a 240 Weatherby with little if any change to the bolt and magazine. Then my search was expanded by sorting through which 6mm cases would fit a 30-06 reloading shell holder which identified the 243 Winchester, 240 Weatherby, 243 Gibbs, 243 Catbird, 6mm/257 Roberts, 6mm BR and 6mm-250, 6mm-284, 6mm-06 variations, 6mm Super LR and 250 Savage. Obviously some of these combinations are wildcats that have not made the jump to commercial production.

The original 244 Remington was a 257 Roberts necked down to 6mm which should work well in a long action rifle especially if it is used for hunting where the overall length might be close to the 2.825 published value for the cartridge. The 244 was renamed after Remington found that their original rifle twist would not stabilize bullets exceeding 90 grains (Remington, I believe, thought the rifle would be used for varmints). The cartridge lost favor and was subsequently reissued as a 6mm Remington that had a faster twist to stabilize the heavier bullets. I would think going to the 257 Roberts would not be an issue. There is a great deal of reloading data and plenty of factory ammunition selections available.

These sites are wonderful because there are suggestions you may not think of or people with similar experiences that can provide you with potential problems that may occur which can save a lot of stress and money. I'd suggest picking your cartridge based on your expectations (purpose), what are willing to accept (e.g., reloading or not), cost and longevity (e.g., barrel life) and then find a gun smith that can build an accurate/reliable shooter that he'll stand behind.

Robert

 

[wboggs]

You can easily convert your LA to a SA with some fairly simple modifications. Contact one of the excellent gunsmiths and they will give you the details.
Personally, I would not even consider the Weatherby, Hawk, Gibbs, etc. A 6mm-06, 6mm-284 and othrs of that case capacity are way overcapacity for 6mm and the additional velocity at muzzle doesn't make up for all the disadvantages. There is a reason why the .243 is so popular.
Bill

 

[Catfish]

Bill,
It all depends on what your looking for. I have acouple of 6-284 and a 224 TTH for long range coyote guns and I very much like the flatter shooting I get with them, in fact I thinking of going to a 22-284 for more case capicity. With some of the new powders on the market you can now make better use of the larger cases. I will admit that burning all of that powder does come at a price as barrel life is shortened, but I get abt. 1,000 rounds through the 224 TTH before I have the barrel set back and rechambered, but I guess if you want to play you have to pay at least alittle extra.

 

[wboggs]

Catfish
You have a valid point. If you want max. velocity and are willing to make the trade offs, something like a 6mm-284 will work. There is a a case capacity limit for each bore diameter above which you no longer increase velocity with more powder. However, you burn out the barrel at a rapid rate. The military has experimented extensively with this but I don't know their data. Some others have used a .378 Wby. case necked way down to try and go over 5000fps. Max. velocity with powder is about 6000fps which is the velocity of the escaping gas. It never reached because you would need a frictionless bore. Again, the military has looked at smooth bores and other propulsion systems.Nevertheless, you can have lots of fun maxing things out and I have done it myself. Bill