I did this almost 25 years ago when I was young and trusted others to be able to recommend and do a gunsmithing job correctly and when I didn't know any better.
I asked a gunsmith if there was a round he could recommend to speed up the velocity of my 243 Win to a gunsmith in Abbotsford BC (I believe he is in Dawson Creek now) he recommended that I ream the chamber of my 243 to 240 Weatherby.
I didn't check the dimensions of the case just handed him my rifle and $100 later he handed it back...
I was heading out on a hunting trip and hadn't had time to reload any rounds so I had purchased some factory ammo when I got out in the bush I decided to give the new high speed cartridge a try.
When I extracted the fired case the result was the first appr 3/4 of the case was a 243 body and a bit of a shoulder then the remaining length was a 240 Weatherby body/shoulder/neck...
To say I was pissed is an understatement so on th eway back home after the trip I stopped in to have a chat with the gunsmith who said "not my problem"...
Me being young and uniformed at the time ended up leaving and putting the rifle away into a closet where it remained for years until Joe Dlask told me of a buddy of his that had a 6mm-284 reamer and could set the barrel back.
Today this pencil neck would have fixed it by rebarreling the rifle with an equal or better quality barrel at no charge to me and it would hav been his highest priority job.
So now I have a 21" barreled 6mm-284 that I originally loaded with the first 90gr X bullets that Barnes made @ 3500fps and now I shoot 70gr Ballistic tips @ 3600fps and 100gr Partitions @ 3250fps...
Don't believe what others are saying the 6mm-284 is an awesome round and I totally recommend it, with 284 Win brass all I do is resize them in a 6mm-284 resizer die and trim a tiny bit off for length and uniformity.
I like the round so much that I am now looking for a s/s 28" barreled T/C Encore in 243 that I can get rechambered to 6mm-284 with a 1-10" twist I should be able to load 90gr Swift Scirroco's to appr 3700fps or better and it will be used as my long range predator rifle that could double nicely as a deer round.
Other than brass was a bit of a problem when only 284 Win brass was available I have never had an issue with this round and would totally recommend it.
Oh yeah absolutely no feeding issue either...
