.270 length from lands

[teebirdhyzer]

I have found a fantastic load for my .270 that is shooting nosler ballistic tips and accubonds sub 1/2" at 100yds. Today I loaded up three sets of bullets to begin toying around with seating depth. I loaded up at .005 off the lands, .010 off, and .015 off. The loads that I had been shooting were actually about .150 off, (3.30" oal, when the length to touch the lands is 3.45") so they were jumping a whole bunch. I'm shooting a really stout load of RL17 with zero signs of pressure so far....should I be concerned with these new loads since they are so close to the lands? hoping to go shoot them tomorrow sometime.

[hub]

It,s real common for BT,s and accubonds seated .050 and even .100 off the lands and still shoot tiny little clusters. The absolute longest I load and still fit the mag is 3.420. Therefore I use 3.400 coal for accubonds and BT,s. So for me I cannot get anywhere near the lands while accuracy with those polymer tips remains very accurate. On the other hand I have a 300 mag. 700 BDL that has a generous mag. that allows me to load a 180 accubond at .015 off the lands. Again accuracy is incredible. Myself I never load any closer to the lands than .015. I,m just not compfortable with closer. At .015 to .020 off the lands I,ve never had any pressure problems with loads that are not already too hot. As always start low and work up.

[teebirdhyzer]

thanks Hub, thats good info.

[1Shot]

..If you're shooting sub 1/2 @ 100 why fool with it..

[teebirdhyzer]

well, that's an excellent question, and one I have also asked myself. One reason is that I have seen one of the groups you posted on here from your .270 where three shots were literally in the same hole. If messing around with the seating lenght doesn't really do any better, at least I haven't really lost anything. Plus, it gives me a good excuse to go shoot it some more!

[1Shot]

well, that's an excellent question, and one I have also asked myself. One reason is that I have seen one of the groups you posted on here from your .270 where three shots were literally in the same hole. If messing around with the seating lenght doesn't really do any better, at least I haven't really lost anything. Plus, it gives me a good excuse to go shoot it some more!


...I hear ya..lol.. ;)..If you were shooting sub 1/2" at .150 off the lands, I'ld move it from there.. .005 at a time +/- your groups will tell you which way to go..I shot this group awhile back before I tweaked the powder on the 1-holer..

...3/100..

http://img.photobucket.com/albums/v692/sqek/270.jpg

[Nor Cal Mikie]

1shot: That's a BR group. ;D Looking pretty good from here. ;)

Tbird: The larger calibers seem to like a "jump" to the lands compared to being jammed.Try a group jammed maybe .010 into the lands and see what you get. Back off from there. Mag length is the only thing to deal with. (single load ;))
1/2" groups at 100 yards is nothing to sneeze at. For a hunting rid, can't be beat.
If you're not showing any pressure signs, my guess is your load is mid range? Good load if the weather gets hot. Lots of wiggle room. ;) And who cares how fast it's going. If they're going close to the same hole, you can depend on it.
You don't have to be fast to be accurate. 8)
I've gone from a jam to a jump on my 6.8 loads and they seem to favor a jump. You won't know what your rig likes till you try. And make sure you change "only" one thing at a time.

[kb7kuh]

How are you guys measuring off the lands? I have always gone by the OAL in the reloading books.

[Nor Cal Mikie]

As far as loading book info, all chambers (throat length/freebore) arn't the same. My throat length and yours may be "very" different.
Split a case neck, stuff a bullet in it long, close the bolt on it and see how long it is. My guess is it's "pretty long".
I prefer the proper tools to get "repeatable" measurements. Hornady/Stoney Point comparator is the way to go. Measure "each" bullet you plan to shoot.
Write down the measurements you get so you can refer back to them often. The throat/freebore gets longer with every round you shoot. Sometimes faster than you think. :o
And it also wouldn't be a bad idea to know the "actual" length of your chamber. Sinclair has the plugs to get that measurement. That way you'll know if you need to trim your brass or not. Just more goodies to help with your reloading fun. ;) Can't have enough goodies! ;D

[kb7kuh]

Looks like the Hornady/Stoney Point comparator is an inexpensive tool and worth picking up.

I will try the split case and see what I come up with for my 270, and the 22-250

Thanks

[fgw_in_fla]

I like to shoot 2 or 3 different types & weights of bullets as I'm sort of an experimenting tinkerer... (did I say that right?)
Anyway, I like to use a spent case that my bullet in question fits in the mouth with just the right amount of drag. I lock it up in the chamber & measure it a few times to insure some kind of consistancy, then crimp it to retain the length. These go into one of those bullet boxes you get from Midway. They fit just right & hold quite a few. I write a little info on the side of the case with marker & use these for length gages. So far they've worked out very well & I made the 'lil woman happy by not spending any money (and it gives me a few extra bucks for powder & stuff).
One more tid bit of info.... I make a new one each time I get a new box of bullets. One of these days I ought to dig out the old length gages & compare them. Just to see if I can determine what kind of wear I'm getting out of the barrel.