204 seating depth

[matto]

I've heard that the 204 likes a jump up to the lands rather then just touching or just off touching. Has anyone played in this area ? And how does it affect accuracy ?

[HiWall]

That would depend more on the rifle than the cartridge I think matto. Each rifle is different and seating depth is a major part of accuracy testing for all.

[trevort]

In my 204 the 39 BKs are seated so the round just fits the magazine. This is way off the lands. you've seen the photos, no effect whatsoever, they are happy to jump.

The 40 gn NBT struggled to get 5 shots under an inch. When seated out so they had to be single fed the group size did reduce but not as good as the BK so stopped fixing something that wasnt broken.

Skipper on the 204um has built a very high spec custom rifle to see just what the 204 can do. He has obtained his best results loading INTO the lands. From my questions on here doing that comes with all sorts of risk warnings

[zzsstt]

He has obtained his best results loading INTO the lands.

Do you mean the projectile is actually "started" in the rifling when the bolt is closed? Such that if the bolt is opened without firing the bullet (assuming it doesn't stay wedged in the barrel) has rifling marks on it?

I'd guess that would require enormous attention to neck tension - or just enormous neck tension - to avoid issues with some projectiles pushing back in to the brass and others with tighter necks pushing further in to the lands, which in itself would seem to bring a whole new bunch of possible variations to the fray.......

[native hunter]

G'dat
Matto- what breed of .204 do you have.???
Regards
Damien webb.

[trevort]

He has obtained his best results loading INTO the lands.

Do you mean the projectile is actually "started" in the rifling when the bolt is closed? Such that if the bolt is opened without firing the bullet (assuming it doesn't stay wedged in the barrel) has rifling marks on it?

.......

Yes thats what he says, I posted a question on the subject but the consensus round here was not a great idea in a hunting rifle whereby you might unload leaving a projie in the barrel and powder thru your action.

[matto]

Thanks for the info guys. I think I will also be loading to suit the magazine. As my rifle is based on a Tikka action with a "MAB barrel" ???
Which has a Boxed magazine so I proberly wouldn't get the projectiles out far enough to the lands anyway. Should have rifle back very soon. Just wondering if the boxed mag was go'n to cost me anything in accuracy. Matt

[trevort]

if my ruger is anything to judge by the answer is "no it wont". nevertheless I bought an action donor and measured the magazine before getting Shane to cut the chamber so I CAN reach the lands and feed from the magazine if need be.