# Rifling lands



## jk3hunter (Dec 29, 2010)

I know this question is a tough one to answer because all rifles are different but I am just curious how far off the lands I should seat my bullet. If this means anything I shoot a DPMS bull 20 in 223. Used a bullet comparator this weekend and found out that my bullets are damn near on the lands if not touching them already! Even though they are touching the lands I still get honest 3/4 inch five shot groups but I was wondering if I seat them back a bit if I can even tighten that up. Any help appreciated.


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## Plainsman (Jul 30, 2003)

Every rifle is different and the only way to know is experiment. If they fit in your clip I would guess they are nt to close to the lands. I had the same rifle as you, it was just to heavy for an old geezer like my to treck after coyote all day long. I traded for a light 16 inch, and that shoots 1/2 inch all day long. My 20 inch heavy grouped under 4/10 inch. 50 gr VMax and H335 grouped right around 1/3 inch. The local sport shot had one ten shot group of .338 hanging under their DPMS's for a couple of months. That was one of my targets from the 20 inch that I purchased from them. 
I didn't like the performance of the VMax on coyote so I have switched to 55 gr soft point. I think they are doing better. If you check Midsouth Shooters Supply, Midway U S A, Nachez shooters supply, etc you will find good prices on plain jane 55 gr soft points. My nephew purchased 4000 and got the price I think under $8 per hundred. 
Anyway, yes I am sure you can do better than 3/4 inch. I never did bother with different seating depths with my DPMS, but I did try different powders and primers. I ended up with Federal match primers and H335 for best accuracy out of Lake City brass.


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## jk3hunter (Dec 29, 2010)

Will H335 perform well in the winter even though it isnt an extreme powder? I use varget which is supposed to be one of the best not being temp sensitive. I know H335 meters well.


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## Plainsman (Jul 30, 2003)

The only way to know is shoot it over a chronograph. I use some varget, but in my 308. I have not tried it in anything else.

H335 I have chronographed down to -10 degrees. I don't know where I put my records, but I think my 22 inch barrel Winchester Featherweight dropped from 3380 fps to 3250 fps. My 16 inch barrel DPMS gives me 3000 fps with a 50 gr and 2980 with a 55 gr. I get 3040 fps with the 55 gr using Hogdon Benchrest. The day I chronographed last year was 5 degrees above zero.


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## jk3hunter (Dec 29, 2010)

i was shocked to find out that my bullets in my current loads touched when seated out to the max that my clip would allow


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## MagnumManiac (Feb 19, 2008)

If you load 20 rounds in 5 round batches going deeper into the case by .005" with each batch, this will tell you if the groups get any better. You could also do another batch of 20 the same way with them even further in the case. 
Sometimes there is a sweet spot that occurs close to the lands and another much further away, anything up to .100", but .050" is more realistic with small calibre bullets.


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## jk3hunter (Dec 29, 2010)

Thats exactly my plan. I am loading 10 rounds each of bullets .010 off and .020 off the lands and possible .030 and .040 later


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## farmerj (Jun 19, 2004)

what ever set-up gives you the lowest Standard deviation / spread when you chrono them if you are going to get all fussy about it.


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## jk3hunter (Dec 29, 2010)

I will be fussy because I am obsessed with accuracy.  I measured my lands five times with a variance of +/- .001 which I was very pleased with. Just loaded up ten that are .010 off. I still cant believe I could touch the lands and still fit in my magazine.


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## Plainsman (Jul 30, 2003)

> I still cant believe I could touch the lands and still fit in my magazine


That surprises me too. I'll have to check mine. Of course I'm just seating to the cannelure in my 55 gr soft point. I'll have to check my VMax since those are seated so I can just get them in the magazine. I thought I was back about 30 thousandths, but I didn't write it down anywhere and I can't remember.


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## jk3hunter (Dec 29, 2010)

with a stoney point bullet comparator I got an average of 2.874 when the round is touching the lands. I backed the next ten off to 2.864


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