JUMP!

686

Over the years I’ve shot a variety of revolvers and most of them have been stamped as being a .357 Magnum.  I don’t play games that require “Magnum” loads so I generally shoot something shorter with a reduced power loading that is easier on the hands and the wallet.  Lately the go to loads have been in Short Colt cases.  The cases are just a bit bigger than a 9mm with a rim on it and they go in and out of my S&W 627 easily.  So far I haven’t noticed any problems but I have heard many a wise old sage posit that there will be a deleterious impact upon accuracy due to the vagaries of “bullet jump.”  Bullet jump is the bullets leap across the vastness of the cylinder as it leaves the case and makes its journey towards the chambers throat.  I picture Evel Knievel attempting to jump the Snake River Canyon when I think of this.  There is my bullet poised upon the precipice, eager, ready to face an uncertain future.  It didn’t work out for Evel Knievel, I’m hoping my bullets have better luck.

short v special
38 Short Colt case and cartridge next to 38 Special case and cartridge

Okay, enough dramatic humor.  It’s pretty obvious that I think “bullet jump” is a bunch of hooey.  At least as far as accuracy out of my revolver is concerned.    I understand that there may be different forces at play when we are discussing rifle accuracy and the distance off of the rifling.  For this test we are talking about a .38 Special at 1.155” vs. a .38 Short Colt at .765 case length.  Sure the Short Colt is visibly shorter but we are talking about .39 of an inch and I just don’t think it is going to make a vast difference in that minuscule amount of time that the bullet is in the cylinder making it’s way towards the throat.

The plan is to load the same projectile over the same sort (but not amount) of powder and the same kind of primer but in the appropriate cases for each cartridge.  I’ll use a .38 Short Colt and .38 Special for the test.  Each one will be fired at 15, 25 and 50 yards from sandbags.  Each load will be using published data.  According to the manuals these loads should yield similar velocities from each of the 2 different loaded rounds.

sw686
S&W 686 6″ bbl

The gun I am using in the test is a no dash S&W 686.  It is an awesome gun but it does have that factory front ramped sight that I have a hard time seeing (this marks the end of the excuse making section).  The 686 has had an action job and has been cut for full moon clips.  For this test I did not use the moon clips.

First up I tried a batch of .38 Specials loaded into Starline Brass and topped with an Armscor 158gr fmj.  I set my target at 15 yards and shot the gun from sandbags.  After the shooting was done I had a 2” group with a flier.  Without the flier it was 1.5”.  Then I loaded the 686 with 38 Short Colts and fired 6 rounds at 15 yards.  This time I had ANOTHER FLIER that bumped my group size up to 2.5” but without that flier I had a nice 5 shot group inside of 1.5”.  I also notice that at all distances my Short Colt rounds did string sort of diagonally whereas the Specials were more of a cluster.

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At 25 yards the 686 kept all 6 of the .38 Specials in a nice 2” group with no fliers.  The .38 Short Colts, or the guy pulling the trigger, fell a bit short here and came in with a group of about 3.25” with a lot of diagonal stringing.  This is still well within the A zone of the USPSA target I was using but the stringing may be due to the “bullet jump” from the .38 Short Colt cases.  At least there were no signs, at any distance, of key holing or other deleterious results.

50 yards is where the “bullet jump” crowd seems to feel that the Short Colt will reveal its weakness.  I hate to tell you that for me, on this trip to the range, it didn’t happen.  At 50 yards with my crummy eyesight and the hard to see factory front sight (please refer to paragraph 4, sentence 2 for my excuse making section), the 38 specials went into a 6” group.  At that distance I can’t really call anything a flier.  I’m sure better shooters than I could shrink that group with the same gun and ammo but I think I’m seeing the results I want from this.  Then I shot the .38 Short Colts at 50 yards and had to chuckle.  I got a 5” group with 5 of the shots in or touching the A zone.  I don’t think “bullet jump” is hurting me on that one.

So a couple of hours at the range and a little time at the reloading bench and I have the answer that I was looking for.  If I’m not hitting what I’m aiming at I can’t blame “bullet jump.”  Maybe the “trigger nut” is to blame?

One final note, I did drag the chronograph to the range just to make sure I was comparing apples to apples velocity wise.  I didn’t record the data but both cartridges made USPSA minor with a little room to spare.  Now, from looking at those pictures I need to adjust my rear sight just a smidgen.  I’m also getting some unburned powder in the .38 Special (note the suet on the fired cartridge in the picture up above) so I’ll have to work on that too.  Oh well, that’ll have to happen on the next trip out.

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Are Pistol Caliber Carbines Shooting “Rifle Like” Velocities?

pcc carbine

I’ve read a plethora of arguments on internet forums regarding USPSA’s adoption of Pistol Caliber Carbines (PCC) in their matches.  Just to be clear we are not talking about Multi-Gun matches here.  We are talking about the standard “pistol” matches.  The quotes around “pistol” are there because the “P” in USPSA doesn’t stand for “pistol” it stands for “practical” and I know that more than a few people got kind of hung up on that.  Whichever way you fell in those debates the fact is that PCC is here, though some clubs are not allowing it as of yet.  I, for one, was in favor of the change.  I mean what’s not to love about a gun that holds 30+ rounds, has little felt recoil, and is capable of hitting targets pretty easily out to 100 yards or more?

Well some people have found things they don’t like in that scenario with velocity of the bullets being one of them.  I read a comment from a long time competitor, and NROI certified official, that he was concerned about the “rifle like velocities” of these PCC guns.  I am not trying to single him out because he isn’t the only one and I guess that for some people it seems logical to assume that there is a large increase in velocity.  I’ve read numerous posts in which someone believes that shooting a 9mm out of a carbine will see dramatic increases in velocity.  I wanted to dispel that notion so I headed to the range with some guns, ammo, and a chronograph.

While I was packing for the range it occurred to me that I needed something with a bit more oomph than my 9mm steel loads so I also packed an open gun that I happen to have around.  It is in .38 Super Comp and I thought it would make a nice contrast to the 9mm steel loads I had made. The gun was built on a Strayer-Voigt Inc. frame and, while it may be an old gun, it still runs USPSA major power factor loads as well as it did when it was new.

I also brought along a Springfield Armory XD(M) 5.25” in 9mm, which is my go to gun for steel matches.  I knew going into this that the ammo I am shooting out of this gun MIGHT, just maybe, be making USPSA minor.  Even though it’s a steel load I do like to make sure those knockdown targets go down.  The gun itself is fairly stock with the exception of a Powder River trigger kit and a Pistol Gear magwell.

The final piece of the puzzle is the Pistol Caliber Carbine.  I built this one myself using a Palmetto State Armory lower that takes Colt style 9mm magazines.  These magazines are basically a modified Uzi mag that holds 32 rounds of 9mm.  It also has the PSA Hybrid Bolt Carrier and a Wilson 1:10 barrel.  Hogue furniture and a POF-USA drop in trigger, both generously donated to matches I attended, round out the rifle build.

The ammunition for the 9mm pistol and carbine used a 124gr fmj from Armscor, Federal small pistol primers and once fired brass.  The 38 Super open gun used a 115gr fmj from Montana Gold, Winchester small rifle primers, and new Starline 38 Super Comp brass.

xdm5.25Once I found a spot at the range I set up my CED chronograph and did a little shooting.  First up was the XD(M) 5.25″ in 9mm.  Three shots averaged 1027 fps.  Not exactly cooking but plenty fast enough for steel matches that don’t have a power factor.

 

 

xdm 5.25Since we are talking power factor I ran the numbers on that and came up with a 127 power factor.  Not too far over the minimum power floor for USPSA minor but it will definitely make it.
Next up we take a look at that 9mm Pistol Caliber Carbine and see how much, if any, increase in velocity we see.

 

PCC 9mmThree shots with the PCC came in at 987 fps. Wait, what’s that, 987 fps?  But that is slower than the XD(M) 5.25″?  How can that be?  Well in all seriousness there are several factors at play here.  The bore on the PCC could be tighter, looser, rifled differently, etc… so there are variables.  Chamber dimensions could also come into play.

 

I’m sure they are both SAAMI spec chambers but, who knows, they could be on PCC 9mmdifferent ends of the specs.  Barrel length could certainly play a role in this as well.  A hotter load may have shifted the results the other way.  Either way, in the end, the carbine was throwing that load downrange 40 fps slower than the pistol.  Which leaves me with some work to do at the reloading bench.  122 power factor is NOT going to cut it.  I will definitely have to check the manual and see how much more powder I can stuff in there to get the speed up.

svi-open1-1The final act of this PCC story is the open gun.  I knew going into this that the SVI would be fast and loud but I had never shot this particular gun.  It belongs to a friend who has often offered me the use of it but, until now, I had always declined.  I’ve owned, and shot, open guns many times but the concussive force they emit, along with the extremely loud report, is always a bit of a surprise when I fire that first shot after so long away from one.

The three shot average  came in at 1511 fps for a power factor of 173.7.  Plenty of room tosvi-open2-2
comfortably make USPSA’s 165 major power factor. Also around 500 fps faster than either the PCC or the XD(M).  Does the open gun have “rifle like” velocity? No, not really.  1500 fps is nothing to sneeze at but it is more like .357 magnum velocity instead of say 30-30 velocity.  To get there we would need to speed things up to well over 2000 fps and I don’t think anyone is interested in that except, of course, 3-gun competitors who are ACTUALLY shooting a rifle and not an overgrown pistol.

So, I think it is safe to say that “rifle like” velocity is definitely off the list of complaints you can make about PCC.  I’ve heard other complaints but I don’t want to get into them in this article.  I will say that ALL competitors need to keep the rules of safe gun handling in mind at ALL times.  Just because your rifle is slung it does not become a “dead stick” as some would put it.  Respect everyone around you and lets all try to have a good time at the range.

 

 

 

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Dillon’s RF100 Primer Filler

97077 RF100 Close-UP

Before I begin a reloading session I have to prepare for that session.   Preparations include the normal checks to make sure everything is set for the caliber I’m loading and doing a caliber conversion if it isn’t (or changing my mind about which caliber I REALLY wanted to shoot anyway…) along with making sure I have an ample supply of all the necessary components on hand.  Then, after everything else is all set, I start filling primer pickup tubes.  I usually have enough tubes on hand to get 500 loaded into tubes so that I can start making ammo.  It isn’t a lengthy process but in the time it takes me to get the job done I could have loaded 100 bullets.  Then, if I’m actually making a lot of ammo, I have to do it again and load all those tubes up.  More time wasted that could’ve been spent making ammo.

Thankfully we have a solution to this problem.   Dillon’s RF 100 Automatic Primer Filler is available in both large and small primer versions and with U.S. and European power supplies depending on your locale.  Here’s the official description from our main website.

RF 100
Dillon RF 100 Automatic Primer Filler

Dillon’s RF 100 Automatic Primer Filler eliminates the task of filling primer pick up tubes. Now you simply pour your primers from their box into the top, press the blue button and watch it run! No need to purchase additional primer pickup tubes.
In about two minutes the primers are inside the protective metal housing. That’s about 30 rounds you can load while the RF 100 is doing your work for you.
The RF 100 is available for either large or small primers, and conversion kits are available.”

 

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