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bushka
05-19-2008, 10:04 PM
Okay, I tried 3 different powders in my 38-56,and am getting 2.5" 15 shot groups
with all 3 powders,bullets weighed,no fillers,open sight apertures @100yds.
This is re-loading 5 fired cases and thumb seating the bullets at the range.
What from here could I do to shrink this in half?

What reduction could I expect to see if I....
trim case length uniform
uniform flash holes
use filler
weigh cases
change alloy [1-20]
change lube [lee alox]
increase/decrease velocity
use a lighter bullet
dry wipe after every 5 shots.

thanks,
B

:castmine:

bushka
05-22-2008, 03:59 PM
Ahhh,I got it.....EXPERIMENT

:drinks:

fourarmed
05-22-2008, 04:25 PM
Your results sound pretty good. I would say that - of the changes you list - the only ones likely to improve your groups very much would be: different bullet, different lube, filler. A change in alloy could cause a slight change in bullet diameter, which could also make a noticeable change.

bushka
05-22-2008, 09:33 PM
Thanks,my Hoch mold is casting an oversize oval bullet that I do not size.
The runout is .003".
The bases are half sharp half rounded though.
I`ll have to get more picky there.
I have a feeling a lighter bullet may be the "it" for this distance/twist.
Also think more velocity will help,but recoil increases also.
I am pushing out very little lead when cleaning after 50 shots,like a few tiny specks on the patch,then nothing,so I think the lube is adequate,but I have an old standby which is SPG and bore butter melted together that literally drips out the muzzle.

fourarmed
05-23-2008, 12:20 PM
A standard part of boolit lore is that less lube can shrink groups. If reducing the amount of your lube results in leading, try a different lube. I have an old cast bullet annual from Wolfe which has an article by Dave Scoville on that. At high velocities with one of the Loverin bullets, he got the best groups with (IIRC) only two or three grooves filled with NRA alox. They could achieve the same groups at slightly higher velocity with only one or two grooves filled with LBT Blue.

bushka
05-23-2008, 11:29 PM
Now thats a contradiction,
how does/can less lube shrink groups?
Is this lube fouling?

MT Gianni
05-24-2008, 01:45 AM
It certainly can especially on a wadcutter. Overlubing does something besides start an arguement, it can be detrimental to accuracy. What or how I don't know, but cutting back lube when you have an otherwise accurate load with a louverin or wadcutter can increase accuracy. Gianni

felix
05-24-2008, 08:56 AM
Yep, either change the lube's characteristics to have less viscosity, or use less of what you are using. ... felix

NSP64
05-24-2008, 09:46 AM
What powders did you use with what boolit? Crimping could give more consistant ignition>higher velocity>better accuracy. OR consistant ignition>higher velocity> worse accuracy. In the latter case your back to square one. If you change anything during experimentation only change one thing at a time, that way if it all goes south, you'll know what happened.:Fire:

longbow
05-24-2008, 10:43 AM
Just another comment on less lube.

While working up loads for my .303 I got lazy and tried dipping Lyman 314299's in melted lube (quick and easy) so the bore riding nose was covered as well - not thick but thicker than with tumble lube.

I found that groups that had been shrinking to acceptable sizes suddenly grew again. Then I remembered reading an article about Schutzen shooters who claimed that too much lube caused bullet "float" so their goal was to use just enough to stop leading and no more.

While I am not in their class of shooting I decided to scrape the lube off the noses of the remaining bullets. Accuracy returned to what I had been getting prior.

The excess lube really has no where to go and is basically incompressible so "float" seems possible. Whatever the reason I don't over lube now.

Longbow

bushka
05-24-2008, 06:02 PM
This could be it, but I wont hold my breath.
I was filling the grooves [neatly] with Lee alox,right at the bench prior to thumbseating and chambering,via my finger,being careful not to get on the bases,or the exposed nose.
Way more was put on, I gather,than the thin coating Lee recommends.
Next batch will be thinned and tumbled.
Powders I am using are unique 13.5/4759 17.0/trail boss 16.0
with Hoch 350grn silohette type bullet.
They all gave same results more or less,unique and 4759 being tie and TB 2nd.
I tried the front sandbag 6" back from the muzzle,but right under the forend was
better as it isnt a heavy barrel.
It is a Smith gaintwist barrel.

I just picked up a new old stock Ohaus 375 255 fn double cav at a show today,
so I may have some data on that one soon.

B

bushka
05-28-2008, 10:03 PM
I casted some of the 375250FN,thumb seated at range etc. imperfect bases -6 grains weight deviation,a little bit of LLA,and

10 shots into 2"@100.
I havnt given up on the 350grain bullet yet,but looks like the bbl twisty no likey as much.

Johnw...ski
05-29-2008, 04:37 PM
Hi Buska,

I recently got a new 35-55 and will be trying it for the first time tomorrow so it will be interesting to compare notes since these are very similar cartridges.

I plan to shoot some groups at 100 yds from a bench with front and rear bags.
The loads will be using a Lyman #378674 335 gr. boolit with 15.0 Bn hardness sized to .377 and lubed with 50/50 beeswax and alox. The boolits have been weighed and are + or - .2 gr. I have not weighed the cases but they are all new and should be the same lot so I don't see a problem. The cases were all at maximum length when I received them and have been trimmed to 2.120". I do not feel it is necessary to ream the flash holes although it wouldn't hurt. Primers are standard CCI large rifle primers but I do plan to switch to CCI Bench Rest primers. I will be using a .060 vegetable fiber wad seated against the base of the boolit. The powders will be Re 7, IMR 3031, and H 4895 to start. I can get my powder measure to hold + or - .1 gr. if I am very careful so I will drop the charges directly from the measurer. The only way to get that accuracy with the powder charges it to get a smooth drop and the same hit on the top and bottom of the stroke, any hang up and the charge gets dumped and recharged.

Well thats about it, I don't have a lot of experience with wads but the gunsmith who built the rifle swears by them so I will start out using them. Oh, if this rifle does not group at around an inch quickly I will not be happy.

John

bushka
05-30-2008, 07:45 PM
Cool, what rifle and sights will you be using? 1" groups sounds like scope territory.Looks like you have a Miller or Haas action in your avatar?
38-55 is a beauty to load for.

Generally I cobble my loads together in the hide hunters fashion,seems to work.
I do better this way then the guys shooting Garands at 50 yards.
the bullet pulls I guesstimate at maybe 3-5 lbs just thumbseating on fired cases.
My Borchardt military model 45-70 did a 6 shot 2" group at 100yds ,open blade and groove, which generally suck as far as sights go,but it did a little better with
preloaded sized cartridges by half,was like an inch,but dammitt-forgot the load!

nextup I will try the same loads,preloaded and loaded out into the throat,
using the breech block to seat them in.maybe some cream o wheat too.

Johnw...ski
05-30-2008, 08:59 PM
Hi Bushka,

I shot a modern version of a hi-wall, it is one of 28 made (see "New Single Shot Rifle in the Single Shot section of this site). The sights are Baldwin long range tang and globe front sights, also the rifle has scope blocks for a 20x
Lyman Super Target Spot scope. So far the iron sights and scope arn't that far apart.

As far as my avatar, that is one of three FDH#2 actions I made designed by Frank
DeHass (see my thread "FDH#2" in the Single Shot area of this site).

Since I am starting to load for this cartridge and a new rifle I am very interested in your results since you are using a similar cartridge.

Today I sighted in using 26.0 gr. IMR 3031 and a 335 gr. Lyman Postell boolit and got some 5 shot groups that had 3 shots touching and 2 others close by for sub
2" groups with iron sights. Then I tried 25.5 gr. Re 7 and 23.0 gr. IMR 4198 and they both gave accuracy of around 4 to 5 " with both iron sights and the scope and were showing signs of leading. The 3031 results with the scope were around 2" at 100 yds. but this was after the leading so that could be a factor.

I will keep you informed.

John







Cool, what rifle and sights will you be using? 1" groups sounds like scope territory.Looks like you have a Miller or Haas action in your avatar?
38-55 is a beauty to load for.

Generally I cobble my loads together in the hide hunters fashion,seems to work.
I do better this way then the guys shooting Garands at 50 yards.
the bullet pulls I guesstimate at maybe 3-5 lbs just thumbseating on fired cases.
My Borchardt military model 45-70 did a 6 shot 2" group at 100yds ,open blade and groove, which generally suck as far as sights go,but it did a little better with
preloaded sized cartridges by half,was like an inch,but dammitt-forgot the load!

nextup I will try the same loads,preloaded and loaded out into the throat,
using the breech block to seat them in.maybe some cream o wheat too.

Johnw...ski
06-03-2008, 03:59 PM
I got out again today and shot the 38-55. Untill I get another mold I am shooting 325 gr. Postell boolits from a Lyman mold. The bore rider on this mold is .005 bigger than my bore diameter so I have to seat the boolits really deep in order to chamber them. I shot 2 loads 25 gr. IMR 3031 with a vegetable fiber wad and
24 gr. 3031 without the wad. Interestingly the load without the wad shot about an inch better than the load with a wad, three five shot 1-3/4" groups at 100 yds with a three shot cluster touching in all three groups. as opposed to three five shot 2-3/4"+ groups at 100 yds.

It's not bad but I'me sure there is more accuracy to be had.

John

NSP64
06-06-2008, 09:05 AM
I got out again today and shot the 38-55. Untill I get another mold I am shooting 325 gr. Postell boolits from a Lyman mold. The bore rider on this mold is .005 bigger than my bore diameter so I have to seat the boolits really deep in order to chamber them. I shot 2 loads 25 gr. IMR 3031 with a vegetable fiber wad and
24 gr. 3031 without the wad. Interestingly the load without the wad shot about an inch better than the load with a wad, three five shot 1-3/4" groups at 100 yds with a three shot cluster touching in all three groups. as opposed to three five shot 2-3/4"+ groups at 100 yds.

It's not bad but I'me sure there is more accuracy to be had.

John

Did you try the 24 gr load imr3031 with the wad?

Johnw...ski
06-06-2008, 09:14 AM
No I didn't try the 24 gr. load with a wad but so far the wad hasn't shown me anything. When I get my new Paul Jones mold and everything fits right I will try the wads again.

John


Did you try the 24 gr load imr3031 with the wad?