Sierra 107 smk in 243 jump or jam?

[NickT]

I’ve been working up a load in my 243 with an 8 twist, and could use a little advice. Do the Sierra 107 grainers like to be jumped or jammed. So far I have worked up a powder load of 42.5 rl19 and a jump of .015 and am getting half minute accuracy. I know my gun can do a bit better. Has anyone had experience jumping then more or jamming them in 10 or 15 thou?

 

[#40Fan]

Mine always shot good at .020" off the lands. If you have the time and can find some, try a load work up of RE-23. I bet you'll find some lovin' around 43 grains.

 

[urbanrifleman]

N160. The end.

 

[Petey]

Every one of my 6mm Kriegers like a .005 or .008 jam, 4 like a .005 and one likes a .008 for the 107 SMK’s. Not sure if it’s practical with your throat or application, but it’s just the ticket for what I do. I always start on touch and found moving in works better than out. More than .008 in has always produced negative results as well. Your barrel will tell you what it likes but that’ll give you a place to start.

 

[TerryPohl]

My 8 twist likes them touching behind Varget
Terry Pohl

 

[Dgd6mm]

Nick, check out the 6mm improved and wildcat forum. In the column on the left at the very top is .243 loads. You may find some good information. You also could go to the search function and possibly find something also. I only used the 107 to fire form .243 brass into 6mm Competition Match brass.

 

[swd]

107's love to be in the lands. Start with the engraving marks square. They frequently shoot extremly well right there.

 

[expiper]

most times accuracy is found with the bullet "touching" the lands,,,however I think it is more dependent on the powder charge than the bullet as to whether to jump or jam,,,Roger

 

[AckleymanII]

107's love to be in the lands. Start with the engraving marks square. They frequently shoot extremly well right there.

+1

 

[abishai]

I have always shot a healthy amount of jump with my 243 and the SMK. That grey ring that can be seen around the bullet hole in the Xring, that's the memory of where your lands used to be.

 

[Mark W]

The 107 SMK load for my 243 RPR started out jumping .025. After close to 1k rounds is probably jumping a little more now but it stil shoots good so I haven’t checked it yet.

 

[tbeasley]

I've found 107smk to like .007 past kiss

 

[Raptor]

Personally I think they will shoot well touching or jammed. I just shot two groups with my 6SLR at 600yds off the hood of my PU that both measured 1.8" for 5 shots and I am jumping them .045 It is a kreiger and has been set back twice. It started life as a 6BRX then re-chambered it to a 6SLR at around 2000rds then shot it for another 1000rds and pulled the barrel. It set for several years then I had it checked and the smith said it didn't have any fire cracking so I had him cut a couple of inches off the chamber end and re-chamber it to the SLR again. At 22"s its a little slow but damn it shoots good!!!

 

[DocDoc]

There must be pixie dust in the air. That is about twice the number of rounds I would expect from a hot 6mm. Hope you can find another like it.

 

[Raptor]

There must be pixie dust in the air. That is about twice the number of rounds I would expect from a hot 6mm. Hope you can find another like it.

I don't get them really hot when I shoot now days I also only push them to right at 3000fps and I used H1000 for over half the barrel life on this rifle. I don't really compete in matches like I used to so I am not burning them down in comps like I used to. Believe me I have went through a ton of barrels in the 6.5s and the 6MMs!! When I go out and shoot now I take two or three rifles and don't let them get to hot then swap out for another. It really does extend your barrel life. Doing this I am getting over 3000rds out of my 284s with a set back at around 1800rds.....

 

[JFrank]

I’ve been working up a load in my 243 with an 8 twist, and could use a little advice. Do the Sierra 107 grainers like to be jumped or jammed. So far I have worked up a powder load of 42.5 rl19 and a jump of .015 and am getting half minute accuracy. I know my gun can do a bit better. Has anyone had experience jumping then more or jamming them in 10 or 15 thou?

Nick
I have a Tikka with a huge chamber shooting smk I might have .090 clearance with box ammo it shoots fine, although better with hand loads .015 off
You may want to test primers you will be surprised at what you discover. 1/4 minute improvement perhaps.
Check the 6br page
J

 

[Curious]

You have to laugh at the replies to this thread otherwise you would cry.

There is no simple answer, you need to try them in your rifle with your load and try them jumping and jammed, nobody here can tell you what your rifle will like with any level of certainty. As things stand you have guys telling you they love to be jammed and others saying they love to be jumped, about as useful as an ashtray on a motorcycle.

 

[mgdietrich]

Jump the,, easy and no worries about stuck round. 0.025 works well

 

[JFrank]

You have to laugh at the replies to this thread otherwise you would cry.

There is no simple answer, you need to try them in your rifle with your load and try them jumping and jammed, nobody here can tell you what your rifle will like with any level of certainty. As things stand you have guys telling you they love to be jammed and others saying they love to be jumped, about as useful as an ashtray on a motorcycle.

Your absolutely right, BTW I just saw a ashtray and a cigarette lighter on a motorcycle the other day " Dude was smoking a cigar listening to his built in stereo what's the world coming to.