TK Moonclip Testing

[b1indfire]

Recently got into revolvers with a 627, and wanted to get some moonclips, but I didn't know which ones would work best with what ammo.

I reached out to TK Customs, and Eli was kind enough to give me a sample pack! So with that, I got to work with my BMT mooner.

 

All results are with my grip and twist strength, which should be about average male in their 20s to 30s on a BMT mooner. No modifications have been made to either the mooner, the moonclips, or the casings. All moonclips tested are 8 rounders for the S&W 627PC.

 

Template:

Ammo brand/type/weight: Best moonclip in my opinion
Blued: https://www.tkcustom.com/products/swn627x8-025-blue
.025: https://www.tkcustom.com/products/swn627x8-025-ss
.020: https://www.tkcustom.com/products/swn627x8-020-ss
Horn: https://www.tkcustom.com/products/swn627x8-025-ss-horn
Star: https://www.tkcustom.com/products/swn627x8-star-025-ss

 

PPU 38 special 158 gr SWC: .025, .020
Blued: Hard to fit last one in
.025: Firm in Firm out, wiggles.
.020: Easy in, easy out, too much wiggle
Horn: No fit
Star: No fit

Federal RTP 130 gr FMJ: .025, horn, .020
Blued: Hard to fit last four in
.025: a little hard to get last one in, but doable, no wriggle (great combo for competition)
.020: Easy in, easy out, wiggles, but loads easy (great combo for practice, possibly for comp)
Horn: Firm in, Firm out, wiggles, but less than the .020, but loads easy (great combo for practice, possibly for comp)
Star: Only fits one at a time, last one is very hard

Armscor 158 gr FMJ: Horn, star, or .020
Blued: Very hard to get in and out. Did not completely load.
.025:  Very hard to get in and out. Did not completely load.
.020: Firm strength required to get first 6 in, last two are very hard, did not completely load. 6 that fit are very wriggly and had lots of space between the rim and the top of the cutout. Likely inner diameter differences.
Horn: Very easy in, very easy out, very loose, one bullet actually was able to move across the middle and touch an opposite bullet when pinched together.
Star: Very difficult to insert, need to be done one at a time, but bullet sits firmly in place when inserted. Did not completely load

Azoom 38 special snap caps: .025, Blued
Blued: Firm in and out. wriggle.
.025: Firmer in and same out as blued, less wriggle.
.020: Easier in and out than blued and .025, much more wriggle.
Horn: Too easy, can be pushed out perpendicularly with a finger. Some rounds fell out directly.
Star: No fit.

Magtech 38 special 158gr LRN: .025
Blued: Load one at a time, otherwise, very strong grip required. Last one incredibly hard to get in.
.025: Slight firm twist. A little wriggly. Would recommend usage for training or competition.
.020: Easier twist. Much more wriggly, Can touch opposing bullet tips with slight pressure, do not recommend.
Horn: Very easy in and out, very wriggly, do not recommend.
Star: Very hard to load, can barely do one at a time. The ones which were loaded do not sit in the cylinder. Do not recommend.

Remmington UMC 38 spl 130gr FMJ: Horn
Blued: No fit.
.025: Firm twist required to get them to fit.
.020: Firm twist required to get them to fit, but easier than .025. Wiggles. Can fall out by twisting vertically.
Horn: Fits well, but one of them fell out by twisting vertically.
Star: No fit.

Winchester Target, 38 spl 130 gr FMJ: .025, .020
Blued: Very Hard to twist.
.025: Firm twist Some wriggle. Somewhat hard to insert into cylinder. Case lip catches on edge of chamber.
.020: Easy in, easy out. Lots of wriggle. Hard to insert into cylinder. Case lips catch on edge of chambers.
Horn: Too loose. Bullets slip out.
Star: No Fit

Federal Champion 38 spl 158 gr LRN: Blued, .020, .025
Blued: Last two require a firm twist. Slight wriggle. Easy insertion
.025: Easy in, easy out. Less wriggle than blued. Hangs up on the edge sometimes.
.020: Easy in, easy out. More wriggle. Very smooth insertion.
Horn: Too easy, bullets fall out. Do not use.
Star: No fit.

 

 

Thanks again to Eli, and I hope this helps someone.

Please let me know if there are brands you'd like me to test. (Fiocchi is on the way)

 

[CSEMARTIN]

TK Custom is a great company.  Eli has been very good to me.

[matteekay]

This is an awesome resource - thanks for doing this!

 

I think the most interesting test would be Starline in the non-Starline moons. 

[MikeBurgess]

do any of the factory loadings actually make minor? I have not tested them myself but was under the impression from the interwebs that they were likely sub minor

[Mcfoto]

Echo that this is a lot of work that will be useful in the future. Just be aware that brass fitting could be potentially a moving target (pun intended). I tested Heartco and TK's designed for Star-line and found them too tight. Came to find out Starline changed their groove. I ordered a lifetime supply so I'd always have the same fit. For my use, TK blued and Revolver Supply plated (.025) are the best. I also went Short Colt (taking the thread slightly off course) which I find the firmness of the fit to moon to be less critical. But I am a pokie D shooter and the M's and GM's on here will have a different opinion.

[b1indfire]

I'd love to test starline, if someone wants to send me some brass

 

@MikeBurgess, apparently some of them do. I found this resource: https://www.gunnuts.net/2010/05/12/factory-38-special-for-competition/

I don't have a chrono to test it for myself, though.
 

@Mcfoto How much brass would a lifetime supply of brass be? I was under the impression that each piece should usually only be used about five times?

[Mcfoto]

28 minutes ago, b1indfire said:

I'd love to test starline, if someone wants to send me some brass

 

 

@Mcfoto How much brass would a lifetime supply of brass be? I was under the impression that each piece should usually only be used about five times?

 

Midway sells 100 packs for around $20. That’d be a good trial. I have 2000 pieces and current usage is less than 500 a month. Remember with moons you get all brass back. Don’t know about 5 times. None of mine have split or failed yet.

[revoman]

I have loaded my Starline 38 short colt probably over 20 times. Every once and a while I will get a split case. At that rate I should never have to buy again. 

[matteekay]

I've actually reloaded Federal 38 Special at least 10 times (some pieces as many as 15+) and I'm only now starting to see the occasional split case. I think it helps that most of us are just making power and not pushing anything crazy-hot.

[mchapman]

16 hours ago, b1indfire said:

? I was under the impression that each piece should usually only be used about five times?

If you are not loading to the MAX every time , you should expect 20 to 30 times of use before failing. A lot depends on how much you are flaring the case mouth, if you flare a lot expect them to fail sooner.

[BallisticianX]

A few variables to case failure rate. Comes down to brand and their quality as companies will use fillers in the brass alloy to cut costs and it results in quicker failure. Then the load and how much it expands the brass. When you form brass it work hardens, or in other words starts to lose ductility. So the more you size the more brittle and uneven the grain structure will become. Now with increased expansion and the greater dimensional correction to resize will accelerate the ductility loss even further. This applies to what mchapman said about case mouth flare. The more you bell that case mouth the more work hardening you induce for a brittle edge.  Another caveat is nickel plated brass; that plating tends to compromise the uniformity in the brass when resized as your compressing a non ductile material into a ductile one upsetting the thickness. Ive found nickel plate brass to last only 50% as long as unplated brass in the same situation.  As far as brass quality, hands down starline. Ive fired more rounds thru starline without failures than anyone else consistantly from lot to lot. 

[MikeBurgess]

As stated above load it till it splits, I ran 2K of Starline short colt for a couple of years and loaded about 20K rounds with it so average of 10 loads per case, I am still using that brass but have added another 2k to the mix. also with short colt I am loading to much, much higher pressures than a 38 spl so I would expect specials to last even longer.

[b1indfire]

Great info! Now I just need to settle down enough to warrant getting a reloading setup.

[pskys2]

21 hours ago, BallisticianX said:

A few variables to case failure rate. Comes down to brand and their quality as companies will use fillers in the brass alloy to cut costs and it results in quicker failure. Then the load and how much it expands the brass. When you form brass it work hardens, or in other words starts to lose ductility. So the more you size the more brittle and uneven the grain structure will become. Now with increased expansion and the greater dimensional correction to resize will accelerate the ductility loss even further. This applies to what mchapman said about case mouth flare. The more you bell that case mouth the more work hardening you induce for a brittle edge.  Another caveat is nickel plated brass; that plating tends to compromise the uniformity in the brass when resized as your compressing a non ductile material into a ductile one upsetting the thickness. Ive found nickel plate brass to last only 50% as long as unplated brass in the same situation.  As far as brass quality, hands down starline. Ive fired more rounds thru starline without failures than anyone else consistantly from lot to lot. 

I always wondered why Nickle Plated Brass didn't last.  It either starts peeling or cracks fairly quickly.

 

 

[MikeyScuba]

One good thing about a revo is I can shoot a cracked case, then toss it.  I’ve got an ever accumulating pile of auto rounds that need to be pulled.  One day...one day.

[pskys2]

2 hours ago, MikeyScuba said:

One good thing about a revo is I can shoot a cracked case, then toss it.  I’ve got an ever accumulating pile of auto rounds that need to be pulled.  One day...one day.

If it's a split case at the mouth I tend to put them last and/or shoot them singly in such a place that I can pick them up for scrap.  

I'm horribly lazy about sorting brass!

 

If it's an incipient head crack, needs pulled.

[MikeyScuba]

Never had a head crack.  When I unclip the brass the cracked ones “sing” in the tube, makes life easy.

[pskys2]

14 hours ago, MikeyScuba said:

Never had a head crack.  When I unclip the brass the cracked ones “sing” in the tube, makes life easy.

I had a buddy tell me he could hear cracked brass ting, or some different sound, when pouing into a can.  Never could hear that.

 

Only pistol brass I've seen with case head issues have been 40 S&W & 38 Supers and those were always bulges.

Seen a super let loose and blow the mag out (right past my head as I was below the shooter who was on stairs).  

 

Incipient cracks are more of a rifle cartridge thing.

[MikeyScuba]

Wow, I’ve heard stories of guns blowing apart but been fortunate enough never to see it in person.

 

After wet tumbling I put the wet brass on a towel and run my fingers through it.  I can hear cracked cases and 38 super “sing”.  Doesn’t work for 380 though but not much of that shot up here.  

[b1indfire]

Here's three more brands I got.

 

Federal Premium Gold Medal 38 spl 148gr LWC: None
NOTE: DOES NOT HAVE GROOVES
Blued: Very hard to twist. Did not completely load.
.025: Very hard to twist. Did not completely load. Was able to get one or two, and removal was easy.
.020: Very hard to twist. Did not completely load. Was able to get one or two, and removal was easy.
Horn: Very hard to twist. Did not completely load. Was able to get one or two, and removal was easy.
Star: Very hard to twist. Did not completely load.

 

Fiocchi 28 spl 130gr FMJ: .020, .025 with modification
Blued: Very hard to twist. Did not completely load. Was able to get one or two, and removal was easy.
.025: Hard to twist. Did not completely load. Was able to get six, and removal was easy.
.020: Required a firm twist on the last two or three. A little wobbly. Removal was easy.
Horn: Very easy to twist in and out. Some rounds were loose enough to not sit in the correcct location. Do not recommend.
Star: Very hard to twist. Did not completely load.

 

Federal American Eagle 38 spl 130gr FMJ: .020, Blued
Blued: Easy in on first 6, last two require a lot of force. Easy out, though. Stiff in place, went into cylinder easy.
.025: Easy in on first 6, last two require a lot of force. Easy out, though. Very stiff in place, hard to insert into cylinder because too stiff.
.020: Easy in, easy out. Wobbly. Easy to load in cylinder.
Horn: Very easy to twist in and out. Some rounds were loose enough to straight up fall out. Do not recommend.
Star: Very hard to twist. Did not completely load. Was able to get one, and removal was easy.