View Full Version : got any .338 advice?
06-07-2009, 09:13 PM
I shot some lee c338-220-1r boolits tonight. They weight about 215 grains and measure about .339 as cast from a mixture of ww and comercial alloy. I wraped them in 2 wraps of traceing paper then sized to .340 in a buckshot push through die with jpw for lub. Accuracy was about 12" at 100yds. I couldnt find any evidence that the patches were coming off. The rifle is a Ruger #1 in .338 win mag. The charge is 70 grains of H4350. Whats the best easyest cheapest way to figure out whats wrong? Thanks Roy
06-07-2009, 10:32 PM
I am far from an expert, but I think that we will need to know how you wrapped them (wet or dry and if wet, what was the patch wet with?)? Did you use anything else (I have read of some people using glue to hold the patch on)? What thickness of tracing paper?
I am using water to wrap tracing paper on some boolits I sized down to .452. With 2 wraps of Tracing Paper the boolit comes up to .460-.461. I do not size after wrapping.
I think that the idea is to have the paper come off the boolit as soon as it leaves the rifle. I was at the range with the rifle (a .458WinMag) yesterday afternoon and all of the patches I recovered were within 10 feet of the muzzle. I have yet to put it on paper for group, but I was consistently hitting 2 inch rocks in the backing mound at 50 meters.
I have noticed that with the water wrapped tracing paper, the paper comes off the boolit very easily if I deliberately unwrap a boolit, but the paper is very stiff and springs back to the shape it was when wrapped on the boolit (complete with grease grooves).
Let us know more about your loads and how you wrapped your boolits and one of the blokes that is really on top of this paper patching thing will be able to help you get better results.
06-08-2009, 02:15 AM
Can you spread a tarp just in front of the bench. T paper will sometimes get repulped and gets hard to find. Some Rugers have a rather abrupt leade and tear the paper as it enters the rifling. I have to extend the paper forward to the point that the front patched portion is less than bore sized.
At least you are hitting paper, it makes it easier to tell if a change made an improvement.
06-08-2009, 05:17 AM
Try sizing the bullet to BORE diameter +.001/.0015, wrapping with 16# WET printer paper. Let dry, lube and then run through your size die. Load and shoot!
06-08-2009, 05:20 AM
It sounds like your final sizeing is a bit too small.
To find out, wipe some valve lapping compound on your patch. Not much, just enough to make a light grey on the paper.
A byproduct, the rifleing entry will get smoother.
I found my final sizeing on my .303 Brit this way. I was close, but had large groups. The same load with the same final sizeing, with lapping compound, I was dead on.
Finding the final sizeing is where the rifle talks. I size my castings twice, once prior to wrapping, once after wrapping.
What is left of JPW is enough lube also.
06-08-2009, 06:07 PM
I dont understand what the function of the lapping compound is beyond smoothing the bore. How will this help me determine the needed final diameter. Do I just start opening up the sizeing die a little at a time? Thanks Roy
06-08-2009, 06:43 PM
When I used the lapping compound, it was really to clean up hammer marks in the bore. The added thickness of the grit tightened up the group. That gave me my final number. It was almost By-Gosh-By-Golly, but it worked.
You can open up the sizing die a little at a time. It will bring the same results eventually.
I had been wrapping to .3135. I got huge groups. The inner barrel had hammer marks all down the bore, and it was potentially a junker so I figuired an experiment might have been in order. I smeared some Lapping Compound on the remaining patches, and fired them.
Little tiny group! Bingo for me.
There was the possibility, the lapping compound performed another function being fired like that, however, I ordered a .314 die for final sizeing. Same groups.
I have stayed there ever since, still get POI results. Actually better than jacketeds of the same weight, and caliber. Even the .312 sized jacketeds do not print that close.
It was an experiment that worked.
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