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#16: Re: How far off the lands !!! Author: chambered221, Location: Lost for good !!!

Posted: Sat Mar 28, 2009 7:12 am
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Also wanted to mention, you don’t need excessive free-bore to run into not being able to seat on the lands!!!
55 or 70 grain bullets in a 6mm Remington are way to short to even consider it.

And once again that brings me to the point I keep trying to make.
Too many re-loaders put to much emphases on trying to seat on the lands!!!

#17: Re: How far off the lands !!! Author: GroovyJack, Location: Bama

Posted: Sat Mar 28, 2009 9:58 am
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I agree with you there on the last point ..

#18: Re: How far off the lands !!! Author: fnuser, Location: S.W. Missouri, U.S.A.

Posted: Sat Mar 28, 2009 11:53 am
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I like what Groovy jack said a couple ago about using the magazine when I first started @20yrs ago I concentrated so hard on making benchrest quality hunting ammo I forgot to try it from the magazine first trip out after I got in the stand I went to load my magazine only to find that the bullets were resting on the feed ramp and the ammunition was binding it was dark and it took me a few minutes to realize what was happening after I got it straightened out I put one in the chamber and closed the bolt only to see a nice 8 watching me fix my gun. He didn't get away but the lesson was still learned. Now I usually try the bullet I've settled on in a fired case with a slightly squeezed neck to find max c.o.a.l. compare that with max mag length I've never had a gun that was factory chambered that allowed a max mag length loaded cartridge to touch lands but always check anyway. I think Groovy was just saying to be practical when researching accuracy in a hunting rifle and not loose track of the function.

#19: Re: How far off the lands !!! Author: Pumpkinslinger, Location: NC foothills

Posted: Sat Mar 28, 2009 5:34 pm
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Changing seating depth changes the distance the bullet has to travel to engage the rifling but it also changes the timing of the exit from the muzzle (Optimum Barrel Time). Which one is affecting the accuracy?? (Things that make you go "Hmmm...")

#20: Re: How far off the lands !!! Author: Dawgdad, Location: On the Prairie

Posted: Mon May 04, 2009 3:33 pm
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Shocked

I may be a bit dyslexic....but it applies to this thread. I have posted that .010" off the lands was a sweet spot for my Competition AR using the 75 gr. A-max.... I re-measured my chamber to check for throat erosion after a season of Highpower competition and it measured 1.990" All last season I had loaded my A-max for 600 yard slow prone believing I was .010" off the lands. I shot some of my best 600 yard scores using that load. I about freaked when I took the measurement because I had loaded the A-maxes to 1.880" I thought the throat was racing away and I would need a new barrel soon. I looked back into my data book and see that I indeed did measure the chamber to be exactly 1.990" last year but I loaded the bullets to 1.880 and called it .010" off!!!! Several hundred rounds of .223 had not eroded the throat at all.. and I have been jumping .110" all the time Embarassed

I almost had a clue when I was trying some 80 grain A max last season and measured them and saw the ogive length was a lot longer for that bullet than its 75 grain brother... I feel like an idiot but it all worked out. God looks after drunks and little children...

#21: Re: How far off the lands !!! Author: chambered221, Location: Lost for good !!!

Posted: Mon May 04, 2009 5:24 pm
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Willing to bet you would have never considered testing .110 off the lands even after you read what I posted !!!

Funny how we learn sometimes !!!

Thanks for being able to share it.

#22: Re: How far off the lands !!! Author: chambered221, Location: Lost for good !!!

Posted: Wed May 06, 2009 4:25 am
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New 1000 yard score record set!!!
Ken Brucklacher shot a 100-8X that measured 3.137 (that’s 10 shots)
.300 Weatherby mag, Norma cases, 240gr Sierra MK’s, 72.0gr H4831, and Federal 215M primers.

There are two reasons why I’m mentioning this.
First, Ken used brand new untouched Norma cases. Not even fire formed in the gun. No case prep what so ever.
Second, Ken last year changed his seating depth from .018 jump to .028 jump. As quoted when asked about this change “really seemed to close the groups”

This is just one more story proofing what I’ve been saying for a long time!!!

#23: Re: How far off the lands !!! Author: Hickok, Location: Thomas WV

Posted: Sat May 16, 2009 5:13 am
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I believe bullet runout has more to do with accuracy. I have checked some factory ammo that had .010" to .013" runout. Didn't shoot worth a crap, 2 inch five shot groups from my .270.

After using Wilson neck dies and fired formed cases in the same rifle, bullet runout was .001" to .003".

Groups dropped to 3/4" range.

I like to seat close to the rifling, but most factory made rifles has such long throats that this is not always possible. I use neck sized, fireformed cases, and try to get bullet runout as low as possible. By doing this, the bullet is held more straighter in line with bore, and starts into the rifling straighter, providing better groups for me.

#24: Re: How far off the lands !!! Author: chambered221, Location: Lost for good !!!

Posted: Sat May 16, 2009 7:07 am
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Hickok wrote:

I believe bullet runout has more to do with accuracy.

I don’t think you’ll get anyone to argue that!!!

In fact it’s my belief that seating bullets deeper in the neck aids in keeping run-out to a minimal.
Case run-out can also cause excessive bullet run-out and needs to be checked as well.

Are you using a the Wilson seating die?

#25: Re: How far off the lands !!! Author: Hickok, Location: Thomas WV

Posted: Sat May 16, 2009 11:36 am
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chambered221 wrote:

Hickok wrote:

I believe bullet runout has more to do with accuracy.

I use the Wilson Neck sizing bushing die on all my rifles except the AR-15's. I also use the Wilson seating die on my rifles. Once I get the necks turned to take off a little brass around about 50% of the neck, and then fireform them to the rifle, and size them with Wilson Neck die, Case runout and bullet runout greatly improve. I don't believe anyone makes a better set of loading dies than L.E. Wilson.

#26: Re: How far off the lands !!! Author: chambered221, Location: Lost for good !!!

Posted: Sat May 16, 2009 3:06 pm
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IMO and like many others L.E. Wilson makes the best dies available!!!
A little slower but the best!!!

#27: Re: How far off the lands !!! Author: Dawgdad, Location: On the Prairie

Posted: Thu Apr 08, 2010 8:37 pm
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I have an update for this old thread about how the sweet spot could be narrowed down in a simple test. I got a chance to try it out with a new barrel on my WOA Service rifle upper. My previous experiences had shown me that I could get good groups using the 75 grain Hornady Amax with 24.5 gr. RE-15 (2750 FPS) by jumping .010-.015” AND .110” . (I discovered that by accident but that is another story in reading a caliper….)

I followed the scheme that Mr. Stecker defined and loaded six bullets at 5 different jumps. I used the Hornady Overall Case Length gauge to measure the chamber length and the cartridge length to the ogive of the bullet. My barrel has a Wylde chamber and appears to have a very long throat. The chamber length measured at 1.920”. The technique I use and have found to be most repeatable is to set the bullet long on the tool then seat the bullet in the chamber and then push the cable up to the base of the bullet rather than seating it short and using the cable to find the rifling.

The lengths I used and the resulting groups are listed below. I was shooting from the prone position using a web sling with a switching 10-15 mph tail wind at an SR target at 200 yards. I am not a high master and using iron sights with my old eyes MOA is about as good as I can do. I fired two – three shot groups and am reporting the better of the two groups but they were very similar for all tests. Mr. Stecker’s article indicated it would be a significant difference in group size, and it was.

+.010” 1.930” Group size – 1.95”– 1.0 moa
-.015” 1.905” Group size – 0.8 ” – 0.4 MOA
-.040” 1.880” Group size – 3.0” – 1.5 MOA
-.080” 1.840” Group size – 3.5” – 1.7 MOA
-.120” 1.800” Group size – 2.9” – 1.5 MOA

The barrel/load combination performed best with the jump of -.015”. This is consistent with other WOA Wilson barreled uppers I have had and those of other shooters I know.

The take home from this.. The wrong OAL can produce a significant difference in accuracy even under 300 yards.

I have done the newberry OCW test on a .243 and will repeat this OAL test using the Vmax bullets on that load.

#28: Re: How far off the lands !!! Author: slimjim, Location: Fort Worth TX

Posted: Fri Apr 16, 2010 12:57 am
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Dawgdad wrote:

Mr. Stecker’s article indicated it would be a significant difference in group size,

Very interesting. Thanks for posting. Do you have a link to this article?

#29: Re: How far off the lands !!! Author: chambered221, Location: Lost for good !!!

Posted: Fri Apr 16, 2010 3:40 am
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It's the link in my original post !!!

Eric Stecker is a master bulletsmith at Berger, I believe he is also involved in their day to day operations.

#30: Re: How far off the lands !!! Author: eaglesnester, Location: Northern Interior B.C. Canada

Posted: Mon May 03, 2010 7:55 am
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I have found that 190 gr Burgers in my 300 Weatherby MK like to be seated far from the leads. Not sure how far off the lands I am as I have not measured as I cant get close anyway because of freebore in all of Roy's Weatherbys.
I just load em so they will feed out of the magazine box as long as I dare and still have good positive feeding. AT 500 yards with RE22 79gr I am getting 3 inch groups all day every day, good enough. I use Burgers exclusively up here in Northern B.C. Canada for all game that I hunt, elk, moose, mule dear, black bear, and grizz.

Cheers & Tighter Groups: Eaglesnester

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