300 win mag 190 match king

[Sheephuntr]

Quick question for you veteran 300 win guys, how far off the lands should I start my load development for the Sierra 190 match Kings? My lands are at 3.509. I do not have the fancy gauge from Hornady, I used a cleaning rod and paper clips measured with Lyman dial calipers about 15 times an came up with that number 12 of the 15 times. This is my first time loading for the 300 and always in the past I went with the book dimensions on length. Any help would be wonderful!

 

[jjmp]

Welcome to our Forum, for many yrs I just Blackened the bullet on a dummy round and found my lands jump that way, as a loose rule try .10 thu's jump or a lite kiss of the lands =.5thu's. off,your way ahead of me using thecleaning rod an paper clip routine , I couldn't get past that lol! happy reloading and enjoy the forums. jjmp

 

[Sheephuntr]

Thanks for your reply! I had a friend of mine tell me about the cleaning rod technique. He didn't really know where to start because he had never messed with a 300 win before.

 

[jjmp]

Your Very Welcome sheephuntr, many many here with more knowledge then me, readings always my best friend , thks jjmp

 

[Sheephuntr]

I've been bumming around on here checking things out for quite a while. I love reading this stuff, only thing that would make it better is if I had someone to go shoot with now!

 

[jjmp]

lol this is the place great on you! sent you a PM. thks jjmp

 

[Bucklowery]

If I remember right I ended up about .015 our and the bolt lift got a little tight beyond that on mine. Sometimes that will get close and sometimes you just have to start from th beginning. The rifle dictates. I have one that loves a big jump

Thanks

Buck

 

[entoptics]

I've found that SMKs in general (variety of weights in 22 and 30 cal) can tolerate a good bit of jump without statistically valid variation in group size. My magazine is short on my 300, so I'm forced to run long jumps (≥ 0.05") unless I single load. I tried single loads around 0.02" off with 175 and 190 SMKs, and they performed no differently than mag length loads of ≥0.06" off.

Any particular reason your going with a 190 SMK? My 300 didn't shoot them any better than anything else (and worse than several), and there's cheaper alternatives with better B.C. Though my gun isn't a tack driver, I've got over 2000 rounds through it (on my 2nd barrel), and I'm of the opinion that the 200+ grain, tipped bullets really are better than HPBT designs.

Some options you might consider, with higher B.C.s that worked as good or better than the 190 SMK for me...

The Hornady ELD Match 208 is easily the best precision of all I've tried, and my ballistics software is spot on out to 1000+ yds.

Other very good performers were the 212 ELDX, 200 ELDX, 178 ELDX, and 200 Sierra GameKing. I initially had great results with the 210 Nosler Accubond Long Range, but it went off the rails for some reason I never figured out after the second box of 100.

The 178 ELDX or ELDM might be of particular interest if you prefer the lighter bullets. I had very good precision, with good agreement between software DOPE and real world, and the B.C. (0.550) is outstanding for something that will do 3100+ FPS in a Win Mag.

 

[Sheephuntr]

Reason I went with the 190smk was it was perty much the first thing I looked at and my grandpa used to shoot alot of sierras back in the day. No real rhyme or reason why. I figured I could learn on these an the rest would only get better.

 

[MagnumManiac]

Reason I went with the 190smk was it was perty much the first thing I looked at and my grandpa used to shoot alot of sierras back in the day. No real rhyme or reason why. I figured I could learn on these an the rest would only get better.

I think you will find that a bit of jump is NOT going to destroy the accuracy potential of your rifle.
Just load your first rounds to be shy .010" of your max mag length, say 3-5 rounds, then load some SHORTER by .005"-.010" and test until you get the tightest group. If you go .010" shorter for 4-5 lots, I'm sure one will be in the 'sweet spot'.
My own 300's, even my comp barrels, are freebored a considerable distance and I get very good accuracy even with .050" jump or more.
A close jump is not always conducive to the best accuracy, only trial and error will prove what works best.

Cheers.

 

[Buck Buster]

Quick question for you veteran 300 win guys, how far off the lands should I start my load development for the Sierra 190 match Kings? My lands are at 3.509. I do not have the fancy gauge from Hornady, I used a cleaning rod and paper clips measured with Lyman dial calipers about 15 times an came up with that number 12 of the 15 times. This is my first time loading for the 300 and always in the past I went with the book dimensions on length. Any help would be wonderful!

First off I only neck size. Usually the best accuracy comes from the bullet just touching the lands or slightly off of them, not always though. All guns are different as far as the bullet they like best, the speed of the bullet, they don't always shoot the best at the fastest speed that you can send them down the tube. You have to play with different variables. As far as seating the bullet against the lands, the way I do it is barely resize the neck of a dummy, maybe about 1/4 inch down the neck just enough to hold the bullet snug in the case. I now start to seat a bullet in the die but not far, I take the dummy out of the die and lay it in my rifle and start to close the action. I will push the action shut with steady palm pressure till I can close my bolt, you now have a bullet seated against the lands. Back your seating die off so it won't seat your bullet farther when you put it back in and run your press down, now you slowly screw the seat down to where it makes contact with the bullet. You can start right there working a load up, all of your bullets will be seated the same. If you want to seat them deeper just screw the inside of your seating die down farther till you find the best accuracy. My 308 Norma shoots great with the bullet lightly touching the lands, and my 300 Win. did too but the seated out bullets wouldn't fit into the clip then. I jest kept screwing and seating till they just fit in my clip. They are a mile from the lands, but shoot good enough for a basic hunting rifle. Just under minute of angle. Good luck hunting and be safe.

 

[Buck Buster]

One more thing I forgot to tell you. I have watched 1000 yard competitors seat each round this way during competition and shoot it. This is where I learned to do this.

 

[DUSTY NOGGIN]

i would say 0.010 off the lands is as close as any new reloader should get until they are certain of their sizing setback measurements at the shoulder -