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I been working up some more loads for my 308..Using the same powder charge,but adjusting the
O,A,L ..Like load 5 with a certain length-5 more with a .010 added length- and 5 more with .020
longer,etc....Have any of you tried this method and if so did you find that the accuracy increased?
I figure the muzzle velocity should stay the same with all the loads..What are your thoughts on this method
of load development...Is it alright or am I going about it all wrong? John:boxing:
Never done much of it, most everything is just set .03125" off the lands.
For less than 500 yard shooting, I personally don't think it matters. My experience shows at my 1K range that my 175 SMK's group a tad tighter at half that distance, but we are talking very small amounts.
Ace that is about the way I do it only I only go .005 per change for testing.I find once I am close I'll change that up to .003 and usually find a very accurate node. Doing it this way I have gone from .75 5 shot groups down to groups in the mid .2's-.3's and I am overly happy with that.
By the way I don't play with powders, I buy IMR 4895 by the 8# jug and find a load for all of my guns with it(8-9 cal.).
I am also not real sure of velocities because I never checked, have a new chrono just to lazy to set it up and I have yet to have an animal tell me the bullet was too slow or fast.
i go from the lands back. that is the way berger said to dowith there bullets so thats what i do . kind makes since though
I am with MOA on this. I do my initial pressure testing and load development with the bullets right at the lands. Then once I find a load I like, I back the bullets out of the lands incrementally. If I started shorter, and then went towards the lands, at some point I would get a pressure spike that could cause problems.
Sean
As the last two posters said, Kiss the lands, find pressure, and rock on.
Not sure if you'll be able to get to the lands in that Remmy John, but in my experience with my 10fp the 175's started grouping better when I moved away from the lands. I worked up a load with the 168 combined techknowledgy Nosler's that shot better than anything I've ever tried just bumped into the lands.
In my mind seating depth fine tunes when the bullet leaves the barrel so if you've got a good charge weight established the groups could tighten a little either way you go. Warning though, if you can hit the lands pressure will increase, that's why I usually start load devlp. jammed, to find the max charge for the rifle.
In my rifle jammed loads don't give tremendice pressure increase, but it could be dangerous if one is shooting a near max load for his rifle then decides to jam in the lands things could go south rather quickly.
Just for a little clarification I always make 1 bullet empty and get my first measurement at the lands, then start coming back in .005 increments.Charge weights start at min. up to max. in .5gr. increments. In 40 years of shooting and reloading I have never had an over pressure issue and only 1 case head seperation( decided it was a bad case).By the time I find my perfect load I will have over 100 rounds down range and a barrel that is nicely broken in ( if one can actually do that) maybe a better term would be "seasoned" like a frying pan.:p
Dan-Froggy.
Thanks for the added info.Appreciate it a lot..I never have played with the bullets
touching the lands much.So I guess it is going to be kind of like a new loading
thing for me..I will start out low and come up...John
What bullets are you using? Berger has an interesting tech article on this exact topic. I couldn't find it on their website, but here is a place you can download the article: http://bulletin.accurateshooter.com/...g-vld-bullets/ .
Out of all my savages all but one of them has a sweet spot at 25 thou off the lands. I usually start there and adjust charge weights until I start getting some decent groups then adjust seating depth in .005 increments up or down to see if groups improve. I only had one that shot the best with the bullets just touching the lands.
I have question for you guys what do you do first O.A.L. or O.C.W. tests?
I guess what I saying is do you get the seating depth first or the powder charge.?
MOA from my experience (15 different savages) I know mine always shot there best at between .018-.022 off so I picked .020 for a starting point and then get my best load. Once the load is established I then go back and start the search for the proper depth,hence the reason it takes me much longer and many more shots than most.
In all my years of doing this only once could I not find either load or depth and that turned out to be a bad barrel and that barrel was propmtly replaced by Douglas with a 3 week turn around. Exceptional CS.
I usually start at the lands then back off in .01 increments. Seems to work. A friend told me to not seat the 175 gr SMKs to the lands and they do seem to shoot better backed off .02". Be careful seating bullets using the OAL because some bullets aren't uniform in length. Better getting a Hornady or Sinclair gauge that measures from the Ogive. If you buy Hornadys then you can also buy the inserts that you can measure shoulder set back so when full length resizing you can choose to bump the should back a couple of thousandths instead of totally reshaping the case.
Be careful when you seat the bullet touching or jammed into the lands. (Probably already know this) Pressure tends to spike when the bullet doesn't jump any.
I read somewhere Brian Litz, Berger's Ballistian, said 0.015 off the lands to start. I loaded 0.003 on either side of the 0.015 off and shot. I did the 0.015 off first, got groups at 0.035 at 100yds. II said to myself my work here is done. I did shoot the others, since it was a nice day and did not do any better than the 0.035 groups. This was with my 10 FP-SR .308.Quote:
Originally Posted by nubrun
I just recently used the Berger method of seating depth test and if you don't think seating depth can help accuracy look at my target. Only thing changed was the seating depth. The #5 group was 0.005" off lands(group size was 0.239") while the #1 group was about 0.130 off. Seemed as I got right there at lands the rifle shot great.
http://i135.photobucket.com/albums/q...f/DSC_1280.jpg
Does anybody measure your .308 handloads with the Hornady bullet comparator that measures from the Ogive to the base of the case. If so what kind of measurements are you getting with the comparator just touching the lands on your savage rifle?
Yes that is what I use to measure my rounds. Depends on the bullet you are using. They have different ogive designs etc....