BP and fouling management for small calibres

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martinibelgian
Posts: 1610
Joined: Thu Oct 26, 2006 1:20 pm

BP and fouling management for small calibres

Post by martinibelgian »

At the match yesterday shooting the 32-20 I had a good example of how important good fouling management can be - and especially its importance with the smaller calibres.

I was shooting my 32-20 (.308 barrel actually, 1:12 twist) at the match. The weather was pretty nice, sunny and little wind. It was barely above freezing, so pretty cold.
My load data:
- R-P case
- Federal LP primers
- 18.4 grs of Swiss no.4
- Card wad
- 151gr 30:1 RN bullet sized at .3085 of my own design

I was wiping with a single moist patch, followed by a dry one. Accuracy for the 1st shots was OK, but gradually degraded, I was couldn't even keep my shots in the 9-ring :? So instead of pushing a single moist patch through the barrel, I used 2, followed by a dry one. Difference was dramatic, all the remaining shots just kept falling in the 10-ring, most even in the X-ring.

As an aside, this goes to show not only the importance of fouling management (which is of course magnified with the the smaller calibres), but also raises a question re. the importance of Chamber/throat/leade design and sensitivity to fouling: This little rifle obviously is pretty sensitive, another barrel I had was much less so, the main difference being a conical freebore section (at at 1.1 degrees instead of a parallel one). Just wondering if that might be the important bit, or something else?

I do know that I am able to shoot blowtubing only PP loads for 13+ shots in my military martini, and that one does have a a serious taper in front of the chamber, and no 45-degree chamber stop. And accuracy remains what I can hold with the stock irons, which unfortunately aren't all that conducive to precision shooting...
beltfed
Posts: 1962
Joined: Sun Jun 03, 2007 10:07 am
Location: Central Wi

Re: BP and fouling management for small calibres

Post by beltfed »

Gert,
As I did on the ASSRA forum, I suggest you look at Bore Critters/pigs on this Forum to be able to wipe
Well and Quickly.
beltfed/arnie
martinibelgian
Posts: 1610
Joined: Thu Oct 26, 2006 1:20 pm

Re: BP and fouling management for small calibres

Post by martinibelgian »

Arnie,

I use them in my large-calibre rifles, so they aren't unknown to me. In this small rifle, action length is an issue even to get the bore pig in. I would need to find .30-cal. short pistol bore brushes to make it work easily. And as it is such a primadonna, not even sure it would have the desired result.
Which doesn't mean I won't be looking to optimize the cleaning between shots.
I already know the bore needs to be both pretty clean and rather dry, at 1st I tried without a dry patch with variable results. Probably because a variable amount of moisture left in the bore. Consistency is the key!
Kenny Wasserburger
Posts: 4728
Joined: Tue Sep 24, 2002 3:53 pm
Location: Gillette, Wyoming

Re: BP and fouling management for small calibres

Post by Kenny Wasserburger »

Dry patch is a non no with Greasers.

PP another story.

KW
We'll raise up our Glasses against Evil Forces, Singing, Whiskey for my men, Beer for my horses.

Wyoming Territory Sharps Shooter
martinibelgian
Posts: 1610
Joined: Thu Oct 26, 2006 1:20 pm

Re: BP and fouling management for small calibres

Post by martinibelgian »

Kenny,

Paradoxically, this is with a greaser. And yes, that's why I refrained from trying the dry patch at 1st. But apparently, in this rifle, the dry patch is a must. The target tells the story. PP is a next try... :D Only have a mould for groove diameter, and up to now pretty mediocre results. But I'm not giving up!
beltfed
Posts: 1962
Joined: Sun Jun 03, 2007 10:07 am
Location: Central Wi

Re: BP and fouling management for small calibres

Post by beltfed »

Gert,
Take a look at the Accurate Molds website:
Number: 30-160P
It is a 0.9" bullet that has two diameters for paper patching for 30 cal bores.
A person can specify diameters on these designs.
You could set up a bullet that would intrude into the 32-20 case maybe 0.100 inch - specify bottom one or two drive bands
for "patch to FF case I.D. so as to allow maximum BP capacity.
Then specify the bands towards the nose for "patch to bore" diameter with paper of your choice.
Perhaps use Seth Cole 55W
beltfed/arnie
mdeland
Posts: 11708
Joined: Mon Nov 20, 2006 1:47 pm

Re: BP and fouling management for small calibres

Post by mdeland »

Was there lead fouling along with powder fouling?
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