Homemade gas check (Freechex) update.

[JeffinNZ]

Team.

I have been continuing the testing of homemade gas checks using Charlie's "Freechex" system. Here is the latest:

To date the aluminium gas checks have displayed mixed results. I have experimented with:

ALUMINIUM:

1) 2 ply soda can wall (2 x 0.0045) 0.009
2) 3 ply soda can wall (3 x 0.0045) 0.0135
3) 1 ply printing plate 0.011
4) 2 ply printing plate/soda can wall (0.011 + 0.0045) 0.0155

Checks have been formed on two diameter mandrels; 0.284 (standard .30cal GC shank) and 0.290 (CBE .303 Brit GC shank) and in a 0.316 anvil to best match .32-20 and .303 Brit, the calibres I am working with.

The best results have been achieved with singly ply printing plate of 0.011 at low intensity/velocity loads using the 0.290 mandrel. This produces checks that are a loose fit and all results thus far have shown that snug fitting checks generate groups of a greater size. I can not be sure why this is so however my speculation is the loose fitting checks are consistently coming off in flight and the snug fitting checks are not dropping from the bullet 100% of the time.

The following is a typical group shot at 50m with my .32-20 Martini action suppressed rifle pushing a Lyman 311316 in air cooled wheel weight over 3.8gr of Unique for 1000fps with the 0.011 alum. checks inside diameter 0.290.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/IMG_0042.jpg

This group is on par with the same load pushing the plain base Lyman 311008. It could be argued however that the 311316 could be shot without a gas check in this load though I have not tried this.

Shot in the .303 Brit at velocities of 15-1600fps the alum. checks of any combination are not 100% consistent in performance. Some groups well shoot acceptable well while others are not as good. I believe this range may be the treshold for the alum.

BRASS:

I have sampled some 0.010 brass shim from two sources. The first was side walls of .22 magnum rimfire cases painstakingly split and flattened for disc cutting. The second was a small sample of brass shim from a friend. Both materials were shot in 2 ply fashion with a single layer of soda can wall to make a 2 ply check of 0.0155 and an inside diameter of 0.284 for a snug fit. Results were much better than similar alum. Tests though still double the group size of commercial checks.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/316240brassFC.jpg

As I have not more brass shim and the labour of love to recover material from .22 mag brass is labourious to say the least I have not progressed further in this medium.

COPPER:

I particularly generous forum member sent me some 0.010 copper shim and this arrived from the US yesterday. As all tests thus far with 2 ply checks have been 'average' in results I decided to work with the 10 thou copper in single ply only. Checks were formed in the 0.316 anvil using both the 0.284 and 0.290 mandrels.

Today I shot both checks at 50m in my No4 MkII .303 Brit attached to a CBE 313 215 GC bullet in heat treated WW over 20gr of AR2205/H4227.

This target is the 0.284 snug fit gas check:

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/IMG_0040.jpg

This target is the 0.290 loose fit gas check; I pulled the last shot low.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/IMG_0041.jpg

Again the loose fitting checks came out on top. The accuracy of the 0.290 ID check is close to on par with commercial Hornady checks and I will be retesting tomorrow weather permitting.

In summary the best results to date have been achieved using 0.011 copper shim in a single ply config. loose fit. Checks are best formed with two blows of the hammer on the mandrel. The first blow is soft to start the shaping and the second blow to form the check and push it free. A single hard blow has a tendency to create lop sided checks.

The following is my set up for forming the checks. Charlie's anvil/mandrel sitting in a recease in a slab off wood held in a vice. When the check is formed it passes through the wood via a 3/8 hole into the can for collection.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/IMG_0039.jpg

More results as they come to hand.

[Lead melter]

It's that southern-hemisphere-reverse-toilet-flush-swirl problem throwing those boolits off kilter:kidding:

[RU shooter]

Jeff ,Nice posting of results thanks! Instead of messing with various layers of AL sheet look at the home improvement stores for AL trim coil or rafter valley flashing comes in various widths and length's the ones I have are .012 for the painted and .010 for the mill finish also take a look in the HVAC section for AL duct sections of the correct thickness Might get some funny looks when you pull the micrometer from your pocket but it beats the heck out of cutting soda and beer cans apart. I recieved my free checker this weekend and honed the hole out to .312 using one disk of the .012 material I get checks that will hold very well to a proper size shank when run through a .311 sizer.

Tim

[docone31]

A picture is worth a thousand words.
I saw a few really good pictures.
I like.

[JeffinNZ]

Team.

Just back from the range. Real cold here today and sleet showers forecast. Windchill was near freezing so it was a rather quick trip. Further the light was very poor do to the cloud cover.

Shot the .303 Brit at a full 100m/110y today. "Freechex" used were 0.010 copper formed on the 0.290 mandrel for a loose fit.

First target is the CBE 313 215 GC bullet over 20.6gr AR2205/H4227 lit by a CCI large rifle primer. 10 shot group with 3 strays for which I have no real reason for other than perhaps the very poor light and my hands being cold. 7 from 10 were in 1 1/2 inches easily on par with commercial Hornady checks.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/IMG_00401.jpg

Second target is the CBE 316 240GC bullet over 24gr of Benchmark (BM2) lit by a CCI large rifle primer also. 5 shot only and I called the low right bullet. Pretty happy with this target and again on par with commercial checks.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/IMG_00391.jpg

It definitely appears that copper (Cu) is the way to go. I really feel the aluminium (Al) I have been using is just to soft. Maybe a harder type of 'Al' might do better.

Weather permitting I hope to test some top end loads tomorrow.

[Meatco1]

Great report !

Thanks Jeff,

Richard

[kjg]

Great job Jeff, been watching and learning as you go, I have been wanting to get buisy myself but just have no time, resorces seem to have gotton low too,and hunting season is just around the corner, and Jeff your work is awesome, THANK YOU. kjg

[JeffinNZ]

Thanks guys. More testing tomorrow.

[JFE]

Hi Jeff, thanks for posting.

One of the things I read about GC's produced using aluminium cans is that they can be used on PB bullets (because they are so thin). Any chance of seeing whether this works and how successful it is.

Joe

[RU shooter]

Hoping to add to Jeffs thread I tried out my home brewed AL checks today.Mine were formed from two different thickness of AL first was the.012 from a roll of painted trim coil the second was .0095 from from a mill finish trim coil. My maker forms the check at .3115-.312 at the base.Both fit the boolit shank snugly but can still be removed with your fingernail with some minor effort. The two boolits I used were the Lee 155-312 and 185-312 the 155 has a shank of the standard .284 and the 185 a hair smaller at .282 . all boolits were sized in a Lee .311 sizer
I loaded 40 rds total up here's a breakdown
155 with .012 GC / 18.0 grs of AA5744
155with .0095 GC /18.0 AA5744

185 with .012 GC / 29.0 gr. 4895
185 with .0095 GC /29.0 grs 4895

I Have had good results with these loads using hornady checks in the past according to my log book,All 4 ,10 rd groups were shot from my 03A3 with issued sights at 100 yds.
The 155 loads both shot extremely well (2moa) the equal to the hornady check in all respects(except mine are FREE:-D)
The 185 loads I got mixed results the .012 GC again shot into 2 moa the same as the store bought check did.But the .0095 thickness shot into two seperate groups of about 5 moa total each 5 shot group was in the 1.5-2 moa range one left one right of POA,Maybe the check or me getting tired eyes I cant be certian without a re test , In a nut shell with the 40 rds fired I had no unexplained fliers(sans the strange last 10 rds.) ,Nor did I have any leading of any kind ,So far I am happy with the results and for my shooting needs they should work nicely and the equal to the store bought kind(I'm free from under the corporate boot of Hornady :drinks:)

Tim

[lordgroom]

What is a good source of .010 copper? I read some where it is available at a hobby store. Anyone know?

[kjg]

good question there,someone mentioned a website not long ago maybe 4 weeks ago? don't remember off hand. kjg

[JeffinNZ]

Good results RUShooter!!!!

I shot at lunchtime today with the No4 Mk2 and will post the photo soon.

I formed 2 ply checks, Cu 0.010 (outer) with Al 0.004 (inner) on both the 0.286 and 0.290 mandrels. Loaded them onto CBE 313 215 bullets over 20.6gr H4227. The 'snug' fitting 0.286 inside diameter checks put 5 rounds into approx 1 1/4 inches at a FULL 100m/110yards. The 0.290 formed checks put the first three into an inch then threw the remaining two high but only 1/2 apart. Most odd.

REAL happy if a little confused at 'snug' fitting previously performed worst.

May have found the Holy Grail over plying up Cu and Al. Better would be 14-16 thou copper but I can't get it here.

I feel the critical factors are:

1) strong enough material for the job - Al alone has not done well for me.
2) checks that fill the void between GC shank and groove 105%.

[Meatco1]

Here's one place http://www.toolsandsupplies.com/detail.asp?product_id=SA+62010

.Another, if you want brass shim (which worked pretty well for me) http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=510-1560&PMPXNO=8913889.

Another place http://www.directindustry.com/prod/precision-brand-products/metal-foil-shim-stock-11842-37960.

Richard

[JeffinNZ]

Team.

I told you an outrageous lie. The group was not 1 1/4 inch. It was 1 7/16. Still pretty good for 100m/110y I have to say. This is easily on par with commercial checks.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/100-0048_IMG-1.jpg

Please remember I have a PH5C sight on my No4 MkII and this group was not shot with military sights.

[dlw]

RU Shooter Where in SW PA.
Dave

[dlw]

Any metal fouling???
Thanks,
Dave

[RU shooter]

RU Shooter Where in SW PA.
Dave
Northern FayetteVam! In the Mt Pleasant /Connellsville area.
I dont know about Jeff but my bore was clean .

[JeffinNZ]

Clean, clean, clean.

Just took receipt of an experimental Freechex in .22 cal yesterday from young Charles.

Hope to run some rounds down the .223 this weekend.

[Euan]

Good stuff Jeff, I'm real keen to see how the 22 check maker goes, as I can use a lot in the hornet night shooting.
Cheers Euan.

[JeffinNZ]

What is the open season on 'nights' down your way and how many on the daily bag........

[Euan]

Giday Jeff,
Some nights can shoot over a hundred or 2 of rabbits and hares. depends on the population etc.
Cheers Euan.

[windrider919]

I have always gotten small quantities of brass shim stock from the automotive stores [sheets usually measuring 5' x 8']. Also, machine shop supply companies stock it in many thicknesses, usually in 10 foot rolls. It comes in widths of 2", 4", 8", 10" and 12". Thickness: .001, .002, .003, .004, .005, .010, .015, .020, .025, ..050, .075, .100, .125. European suppliers will roll theirs in mm. You can also get it in stainless but I doubt that would make very good GC.

Here are some links for shim stock. Note the brass will usually be 'Half-hard' alloy with about 40% zinc

www.aloma.com OEM SOURCE

www.precisionbrand.com OEM SOURCE

www.mcmaster.com One of the worlds largest ind suppliers

www.sdp-si.com supplier

www.shopaid.com supplier

www.grainger.com Big US ind supplier

ETC...........


I can not understand why for months I kept seeing the question asked on where to get shim stock. Remember when in the movie Star Wars it was said "Use the Force, Luke" What that really means is "USE THE INTERNET SEARCH FORCE, Bubba'. Just Google, or Yahoo or MSN 'shim stock" and GO!

[JeffinNZ]

Thanks for the info but you must remember I live in New Zealand and things are VERY different down here. It wouldn't be worth me having it posted in from the US so I make do with what is around.

[windrider919]

I understand and thoroughly sympathize. Having been to Christchurch as a Tech Rep for GE i feel your pain. However, people get the government they deserve. I had such wonderful experiences with the brain dead bureaucrats that I declined to ever return. I was especially impressed with the customs people who failed to understand that the more they tried to make my life difficult the more their lives would suffer. As I told them: "You are paying me $480.00 a day Travel & Living, a rental car and my pay for 12 hours a day even days I don't work and am on standby. The parts you are holding are not mine, they are not GEs, they are yours. Prepaid for and all I am here for is to install them. I can stay here al long as you like because every expense, 100% is just billed back to you and your government and citizens. So your game of 'Silly Buggers' is just amusing and you have failed to punish me for your obvious prejudices against Americans, well illustrated by you snide remarks. You have told me that my boxes will not be available for 5 more days and it will just be sitting in a warehouse. I have been working and on the go for over 6 weeks without a day off, see you in 5 days." And I left. Greatest scenery in the world. Best hunting ever on South Island. Worst hotels in my life with small, dark and drab rooms and the food was like something in an old fokes home. I still enjoyed my paid vacation on the NZ citizens expense. Even the yahoos in Italy, Guatemala and Nicaragua got the message but those crats down under never did.

So I am absolutely sure that your access to the world is limited and you really have to scrape by and make do. That sort of thing is a powerful driving force for innovation. Love your posts and the experimenting you are doing benifets all of us. Best of luck!

[Piet]

Hi Jeff,
Maybe you have already tried it, but what about using Zinc. I remember an article in Handloader's digest bout a Zinc washer swaged to a bullet.

Piet

[JeffinNZ]

Team.

More testing today. The following is a group shot at 100m/110y with my No4 MkII using the CBE 316 240 bullet and a 2 ply Cu 10 thou/Al 4.3 thou Freechex.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/IMG_0081.jpg

Damn last shot jitters!!!!!!!!!!

The next group I am fully prepared for you all to "poo poo, yeah right, don't believe it, were you drunk" comment on but I sit here and tell you this is 100% true. 100m/110y, CBE 313 215 bullet and the same check. I had run a couple of dry patches down the rifle after the last range visit to see if all was well in the bore. Took two shots to bring the old girl right again and then the final three.............well, see for yourself.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/IMG_0079.jpg
http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/IMG_0080.jpg

Can't say it will ever happen again but I swear that this is 100% true.

[Bigjohn]

Jeff; Some people tend to poo-poo things without thinking. That test would have been good to have tried without the cleaning; sometimes takes a shot or two, to re-foul the barrel to previous level and return the good grouping.

Once I have the sights adjusted for where I want the group to be on the target; I don't check the progress of the group until after the last shot.
I had a range experience many years back when launching some RCBS .308-165-SIL through an OMARK 44B over the bench rest. After the fourth shot a bystander who was watch through my spotting scope called for me to have a look. I told him I would when I had finished shooting the group.
The group ended up as a single hole in the target @ 50metres, 3/4" high by 1/2" wide.

Unfortunately; many of my early records were lost some years back as the result of a brain fade but what I can remember is; RCBS 308-165-SIL boolit cast hard (range salvage) sized .309", seated in front of a load of REDDOT, weight ?? of charge and ignited by a Berdan Primer RWS 5.5mm.
This was shot over sandbags (which was all I had at the time) off the bench we called Ol' Shaky because it leaned which ever way the wind blew at the time.

I must add that I have been trying to reproduce this group ever since.

John.

[1Shirt]

I bought the 30 and 44 Free check tools, and have been playing with mostly the 30 checks and the Ranch Dog blt. So far testing has been limited to 30-30, and 308, and results while not very conclusive shows little difference in accuracy with loads tested to date. The 44's seem to have a slightly shorter side than commercial, but might be my imagination, and will be giving them a workout in 44 mag and 444 in the near future. Am using tooling copper from craft stores initially, but will be trying coke cans in the near future. Interesting reports, and the more research put into this issue the better with rising prices, not to mention something that goes just one step further in making home made ammo just that rather than something that is just assembled.
1Shirt!:coffee: