Think you will find that the sleeve will give you a more consistent and larger bedding area for a large cartidge such as the RUM. 700 action is not noted for being stiff either and the sleeve will certainly stiffen it up.
However having said that. By the time you figure up the cost of a 700 action($300-350, truing($75-100), lapping lugs($25-40), sleeving$250-300), Hart/Sinclir bolt release ($60-80), etc, you can buy a custom action that will have twice the resale and cost less money than what you are proposing.
aren't the Nesikas the same thread as a 700 rem action? If so, I guess a replace and rebed would be possible then?
I am going to be shooting this rifle and learning my wind and trajectory for probably the next 2 years, and then try some competition. I am hoping this will provide me a good learning platform so that i can go into the LG benchrest and try my hand at 1000yds. That being said, this should be a good start right?
The nesieka's action threads are different from the 700 action. The nesieka has more threads,don't remember specifically, so if you decide later to put the barrel on a neseika after it is chambered for the 700 you will have to chop off at least an inch and rechamber.
Sleeve costs about $180-200 and another $80-100 for gluing on.
Bolt release is drilled into side to allow pushbutton release for bolt in competition instead of taking something sharp and pushing down on the Rem release inside action. In comp you have to put in and take out bolt while on line.
You can sell your action for $300-350 on Benchrestcentral.com or xtremeaccuracy.com anyday.
Take it for what it is worth, I have gone both ways and will now mainly stay with the custom actions and in particular for magnums and large calibers. Only way to go.
Look at viper or neisaka(?) actions for starters. Vipers are getting to be popular with 1000 yard guys. Cost about $850 starting same with Neisakas.