Sunday, August 21, 2011

Part 4: Using The Ladder Test - H110 Results, Also - Extreme Alox Defined

It's been a few weeks since starting this series.  Here is a review of the H110 Ladder test.  If you haven't been following along, please go to Part 1 and start there, otherwise this won't make sense.

First, the ladder test results using the Lee TL-358-158-SWC bullets, now dropping at 168-170 grains.  I modified the mould by lapping it, which is described in a earlier post.

Based on this ladder, 13.5 grains is the sweet spot, now to test it out.

Testing the 13.5 grain load:  The test revolver remains a Ruger 357 Blackhawk with a 6.5 inch barrel, and stock open iron sights.  Shooting groups at 25 yards, even off a sandbag rest is a challenge for me.  I included a quarter as a reference, the target sizes are completely different in these photos, with this one being 1/2 the size of the ladder test picture.

I've started shooting off-hand (unsupported) and more rounds in each group for these tests.  This is one great result, for me, the variance is all shooter induced.  The iron sights make it difficult to shoot every round in a tight group, but I seem to be improving.  Even though it might not look like it to some of the readers. 

The results of the tests have shown that the Ladder Test WORKS.  At least in a longer barreled 357 magnum.  I do plan a test with a 38 special snub-nose, but not as part of this series.

If you want to work up loads quickly and effectively use a Ladder Test.  In one session, with as few as 5 rounds to 9 rounds, you can identify sweet spots with a given powder.  

Refining the charge at the sweet spot is completely up to you, but I have yet to improve the cartridges accuracy beyond the test result.  During this test, great loads using Unique and H110 were discovered for both bullets used.  The Lee TL-358-158-SWC and the 358-429 from NOE, both are lapped.  700X was shown to not work in my Blackhawk (see Part 5 for more about 700X & fast powders in general), even though my Taurus 66 loved it.

Extreme Alox Described:

The Blackhawk shot the TL-358-158-SWC accurately from day 1.  However it starts to lead at 10-20 rounds and looses accuracy at 40 rounds.  At this point, the bullet isn't a viable option for this gun.  The leading is right at the start of the lands, extending 1/8-1/4 inch.

I decided to see if it would ever shoot without leading this bullet, without fire-lapping the gun or modifying the gun in any way.  I've gotten great results fire-lapping in the past, but it's not guaranteed to fix this problem, and once some metal is removed it can't be added back.  So instead, I decided to test different way to lube with liquid Alox.

First, the Lee instructions for a standard application leave a very thin coating of Alox.  This is the proven and standard way to lube using liquid Alox.  Since that didn't work, I went non-standard, so this Extreme Alox (my term for the process) is to address a problem.  If you have a similar leading problem, give either of the two approaches a try.

Extreme Alox 1: The Blackhawk has no leading in any load with the 358-158 any more. By applying a heavy coating of Alox and Mica, it shoots everything from puff loads to full magnum rounds leaving a shiny barrel after 100 rounds.  The steps to apply this heavy coating are:
  1. Apply first coat of straight Alox, making a Z shape across the bullets, tumble, spread on wax paper and let dry overnight.  This is a heavier coating than Lee recommends
  2. Apply the second coat of straight Alox, just like step1
  3. Apply a medium amount of Mica and shake around (see the tumble lube post)
This will result in a very heavy coating, however one single coating didn't work.  It took 2 coats of liquid Aloxx and the Mica to resolve the problem.  You will need to check the bullet seating and crimp dies every 100 handloads.  Any buildup should be cleaned out using mineral spirits or another good cleaner.  If you don't do this the buildup will eventually make a mess, and seat the bullets deeper.  That can cause accuracy and potentially pressure problems.  This is my preferred solution and what I use.

Dillon has dies designed to pop out for cleaning, then be put back, all without messing up the adjustments.  They aren't cheap, but they are very well made and make cleaning a no-brainer.

Extreme Alox 2:  Dipping the bullets into Alox also solved the leading problem.  Alox applied using this technique is probably the most effective I've seen.  That's the big plus, the negative is it's slow and takes patience.  Rather than detail the how-to, here is a link with great instructions:

If your revolver is super accurate with a tumble lube design, but has a leading issue, it may need to be lapped to the correct size.  In my case, the leading was minimal and the size wasn't an issue.  So Extreme Alox solved the problem and continues to leave a shiny barrel.

That's a wrap for today.

Have fun and shoot tight groups!

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