Wednesday, June 29, 2011

Update: The Best Way to Tumble Lube the Best Cast Bullets

Lube testing with 357 magnums has produced some fascinating results. This is an update on the prior lube posts.

For target loads with fast powder:  The top 2 tumble lube variations of lube are JPW/Xlox mixed 3/1 and also pure JPW.  They are so close in performance and accuracy that they are really equivalent.  The JPW/Xlox (or LLA, it doesn't matter) gets the very slight nod because the best grouping I've ever shot used it.  Also, after shooting many groups and taking all the measurements, the results are, on average, within .1 inch of each other.  That's from 25 yards off a rest.  This shooter isn't good enough to call that conclusive.

This is with the Lee TL358-158-SWC, lapped to drop 166-7 grain bullets.  The most accurate design for a light-fast-powder load in a 357 magnum. (another test result is coming...)

Added later:  I'm using up the Xlox/Alox that I have, using it to stretch my JPW.  Once it's gone, I'll be using pure JPW again.  I just hate to waste anything.

  • Note:  Tumble lubing standard groove bullets, for the light loads, may work well.  However I haven't spent much time testing this combination.  There is no leading, but accuracy may drop off.  It would be slight, less than 1/4 inch at 25 yards.  But that's speculation, since I haven't found a better more accurate bullet.  I don't plan to test this more.  Shooting less accurate bullet designs is not high on the list of ways to spend my time.

Heavy magnum loads using slow powder are most accurate with a heavy bullet.  Using a 358-429 lapped mould, that drops 178 grain bullets has proven to be the most accurate.  Using Darr lube has produced the best results with this combination.  Other conventional lubes may work too, there are too many to test them all.

NOTE: Tumble lube on a large-groove bullet, with a magnum load, is proven to loose accuracy.  This is not speculation.  Up to 1/2 inch at 25 yards.  Not that the TL fails to lube as there is no leading.  I suspect the huge empty lube groove doesn't support the bullet base adequately.  Causing the accuracy to drop off.  That is with very soft bullets, so it may not apply to shooting WW or harder.  Since the harder bullets have also proven to be less accurate, I won't spend time doing additional tests with them either.

Some general comments:  That doesn't mean tumble lubing a with a small conventional-lube-groove will be less accurate.  But it might, at longer distance.  If you measure 25 yard groups with a caliper, and care about fractions of an inch in group size, it's worth testing.

If you shoot at 15 yards and do an eyeball, "looks good to me", you probably can't tell the difference so it doesn't matter.

The results in your gun, based upon lube groove design, lube, alloy, and charge should be similar to mine.  Or said another way, a huge lube groove (like a Keith) with a soft bullet and TL may not be the most accurate combination, depending on the charge.  So try it out, at some distance.  When a tumble lube design proves to be extremely accurate, try some JPW/Xlox 3/1, or pure JPW.

I hope this is useful information that helps you shoot tighter groups with your 357 Magnum.

Sunday, June 26, 2011

Newly Added Hodgdon Load Data, and Benchrest Bags (Big Boy Bag)

Load data from Hodgdon continues to be the primary source of load data for my loading needs.  The 357 Magnum Revolver and Rifle recipes are incredibly helpful, even though not every bullet weight has cast recipes. I admit to working up the jacketed recipes with cast.  Work up the charges slowly, looking for pressure signs, keep the changes small and be safe!  Before reaching the maximum charge accuracy often falls off, depending on the powder.

Hodgdon recipes are THE reliable source when loading Hodgdon powders.  I do have several others manuals, but they always get checked with Hodgdon as a "failsafe".

Don't exceed the maximum charges, work up to them slowly and you'll get the most from the powder.

The most accurate loads are often light and well below any potential pressure problems, so they are not an issue.  H110/W296 (they are the same powder) and Lil'Gun are the slow burners and high velocity powders.  They do best at the upper end, so work up carefully and you'll be good.  H110 has proven to be incredibly accurate, provides high velocity, and around here is easy to find.  It's the only magnum powder in my powder cabinet.

The only thing I don't like about the Hodgdon charts is that the data isn't sorted by velocity.  So below are 2 links, one for 357 Magnum Revolvers and one for 357 Magnum Rifles.  Each is sorted within a bullet, by velocity.  I've found this to be very helpful when deciding which powders to test.  Its a small thing, but very helpful.

Also, the powders recommended by Hodgdon are what they have listed.  You will notice many are missing from the Rifle data.  That doesn't mean you can't use them.  Just that Hodgdon believes they don't work as well in a rifle.  You may not agree.

Load data sorted by Velocity for each Bullet:

357 Magnum Revolver Hodgdon's Recipes

357 Magnum Rifle Hodgdon's Recipes

Big Boy Benchrest Bags:

These posts are all about accuracy when casting, handloading and shooting 357 Magnums.  My approach is to test a few loads at a time.  The results are measured with calibers and force ranked, top down.  The best performers are then tested against other "best performers".  All at 25 yards off a rest.  After many thousands of test rounds, my rolled up carpet "cheapo" rest is retired.

I've bought a few other rests, and didn't like them.  After searching high and low, here it is.  And wow!  I love these bags.  I filled them to be softer than pictured.  They've been working out really well, so I though I'd pass along the info about the Big Boy, Flat Bags, and Rifle Stock Squeeze Bag.   These aren't my guns, but are from the manufacturers website.

These bags a AWESOME!  Fill them to meet your needs.  Soft or more full for a firmer rest.  Flip them, stack them, put them on their side, it all works.  Did I mention how great these are.  Look for your self:

Shoot tight groups, and have fun with your shooting.  Oh, a great ballistics spreadsheet for the most accurate 357 Magnum loads is coming soon, stay tuned.

Sunday, June 19, 2011

For a Change of Pace: Good Group With My Rossi M92 Carbine Lever Action, 357 Magnum of Course, Part 2

Two great magnum loads for the M92, 357 magnum carbine have risen to the top of the accuracy chart.

First, the 2 moulds that are producing the most accurate bullets in the Rossi are also my 2 favorites for the revolver:
  • 358-429 NOE, lapped to drop .3604 bullets with BHN 7 alloy.  New weight is 178-179 grains (I'll call it 180, after the recipes that suite it best)
  • TL358-158-SWC Lee, lapped to drop at .3604, also with BHN7 alloy.  New weight is 168 grains
The NOE loaded over 13.5 grains of H110, with a heavy crimp, Darr lube, and a 1.620 OAL shot a 4 shot group of .33 inches.  I estimate the velocity to be 1,400FPS.  Measured center to center, 25 yards off a rest.  Yeah I know, it's not much distance, but it's what's available to me.

This load just beat the Lee, lubed with JPW, over 3.5 grains of HP-38.  The same 3.5 charge, but with 700X is right there as well.  The HP-38 load shot a group of .34 inches.

With a slightly bigger grouping of .67 inches is the Lee, lubed with LLA/MS & Mica (detailed in the Tumble Lube post) over 15.5 grains of H110 and a heavy crimp.  Wow, impressive round to shoot. I estimate the velocity of this load to be 1,700 FPS.  The H110 works just a bit better with the 178 grain bullet.  So I mention this because the 358-429 mould from NOE is only available during group buys, or used.  The Lee is easy to get.  If you can't get the a 358-429 that you can lap (steel and iron are tough to work on) the Lee 158, lapped, is a great option.
The other mould maker can listed on the right can custom make you a 358-429.  Check them out.

It's worth noting that the lapped moulds are producing the most accurate ammo.  For my 357's that is a bullet that drops from the mould at .3604 (roughly), and then sized for consistency to .360.  The Keith works best sized and lubed on a lubrisizer.  I like to size the Lee in a custom sizer (order directly from Lee for $35).  Magnum loads get lubed with the LLA/MS and mica, while other loads get straight Johnson's Paste Wax.

A BRP 158 Hornady clone mould is here too.  It's very high quality, an excellent mould.  Preliminary results are looking great.  I'm looking forward to working with it and will be reporting the results. 

Sunday, June 5, 2011

For a Change of Pace: Good Group With My Rossi M92 Carbine Lever Action, 357 Magnum of Course, Part 1

Hi everyone,

I started this as a revolver blog, however from time-to-time I'll sneak in a post about my 3 month old Rossi M92, 357 magnum carbine.  It's the round barrel, 20 inch version.  The picture below is how it came from the factory.  I added a Rossi weaver mount and a handgun-Simmons 4X scope.  It was easy to do as Rossi does make the mount, and the rifle is pre-drilled below the stock sights to fit it:

I've been working on some loads for this sweet shooting rifle, and getting some good results.  It's tough to say just how accurate at a longer range my loads would be, as I shoot almost exclusively at in indoor range.  The limits distance to a short (for rifle) 25 yards.

So far, everything that shoots well in the 357 revolver shoots well in the rifle.  But there are some loads that only work well in the Rossi.  I'm definitely a rifle rookie and don't have a lot of high-end equipment such as a Ransom Rest, and when shooting groups use a rolled up carpet as my low-tech rest.

Anyway, here is a 5 shot group, the best by about .1 inch.  The high shot was the first.  The next 4 rounds went into the other hole.  Center to center the 4 shot hole is .3 inches.  THAT'S FUN!  Even if it is 25 yards.

Oh, this is with a Lee TL158-SWC, BHN 7, .360 diameter, JPW lube, 357 brass and 3.5 grains of HP-38, OAL of 1.60 and medium crimp. 

I enjoy casting and loading for the revolver, and now the rifle has added to the fun.  357 rifles are a blast to shoot, everyone needs one.  Light 38 special loads just put a smile on my face.  So do full-house H110 loads!

If you are thinking of a new rifle, one to have some fun with, take a look at this Rossi.  If you do, check out Steve's Gunz (link on the right), his DVD is a must have.