Homemade gas check (Freechex) update.

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  • Last Post 13 December 2008
JeffinNZ posted this 07 August 2008

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.

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:

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.

Cheers from New Zealand

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JeffinNZ posted this 07 August 2008

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.

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.  Made a harder type of 'Al' might do better.

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

Cheers from New Zealand

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codarnall posted this 08 August 2008

I suppose I am could be considered biased but you have got to love this collection setup. Charlie

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JeffinNZ posted this 08 August 2008

It's the Kiwi way Charlie.  We are specialists in “making do".  Comes from living at the bottom of the world.

Cheers from New Zealand

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CB posted this 09 August 2008

Jeff What lube are you using? Have you noticed any lube spatter on your targets?

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CB posted this 09 August 2008

Jeff in NZ,

Very interesting posts and great pictures. A lot of us, shall we say thrifty, cast bullet types are interest in the Freechecks is is great to have you doing all the hard work.

Good luck in finding the holy grail or the united field theory of Freechecks.

John

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JeffinNZ posted this 09 August 2008

Jeff Bowles wrote: Jeff What lube are you using? Have you noticed any lube spatter on your targets?

Hi Jeff.

My own “Beaver Grease".  Can't say I have noted splatters but will have a look.  Going to the range again soon....................soon as a frost thaws a bit......sheesshh.

Cheers from New Zealand

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codarnall posted this 09 August 2008

Jeff:  I bought .005” brass a 4"x10” for $2.29, .005” copper (soft) 11.99 12"x30".  I'm sure those are high prices.  I cut strips a hair over 5/16"  with my paper cutter, except for where I wasn't a hair over I made 14 perfect .224's per strip.  I'm sure the hand held (on order) McGill 5/16"( for about $4. ) punch will work great and faster too. My old German 1/4” paper punch goes though the metal like butter and crisp clean disks result. Metal vender is K&S metals http://www.ksmetals.com.>http://www.ksmetals.com. ;) Charlie

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JeffinNZ posted this 12 August 2008

I shot at lunchtime today with the No4 Mk2.

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 1 7/16 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.

Cheers from New Zealand

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JeffinNZ posted this 17 August 2008

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.

Cheers from New Zealand

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CB posted this 17 August 2008

I fully believe that group, have done it myself on occasion.

In a match last month I had a ten shot group that was .712 and I had another at our match yesterday that was .808...

I have seen 5 shot groups that measured under .250...

What I do find interesting is the fact that you are using a dual material homemade check.

Is the check coming off in flight? Have you tried to dig one out of the berm to see if one layer is still attached?

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JeffinNZ posted this 17 August 2008

Thanks Jeff.  The thing is most Lee Enfields won't do that at 25 let alone 100m but as I said it will like NEVER happen again.

I don't know if the checks are coming off or staying on but it most be either one or the other for success good results.  Very hard to recover the bullets at my range.  Trust me, if I could get me lead back I would!!!.>

Cheers from New Zealand

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CB posted this 17 August 2008

Those Lee Enfields can shoot if you treat them right. All you gotta do is threaten to start shooting cordite out of them again, it is amazing how they will snap into shape then.

It is a shame you cant reclaim your lead, We clean out our berms every other year, keeps me shooting.

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JeffinNZ posted this 17 August 2008

Ah yes, the threat of the dreaded English barrel dissolving rods.  Every bullet needs to be progressively longer to take up the slack in the throat!

Just tried the 2 ply 0.005 Cu/0.010 Al checks and they went really well even though there is a roaring southerly outside.  Will do some more testing soon.

The reason I shoot the 2 ply checks is I can't find 15-16 thou copper here.

Cheers from New Zealand

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gary hartnett posted this 13 December 2008

gday i know this is  an old topic  but i just cane across it and thought that i would add myt 2 bobs worth. i have several enfields  ,a couple of 3s, a 4 and a martini enfield. 2 of the 33 have worn barrels and the martini is clean bright but woe full. 1 of the 3s and the 4 look like they have just come from the factory and shoot copper jackets into an 1” group at a 100 yards off the bench,all my rifles have full would but all have some kind of beddind an barrel work. the rifles with the worn barrels spray copper jackets with heart braking consistency. so in frustration i turned to the net and came arcross ed harris post and the topic on the “load". have a large amount of pistol power but no red dot on hand i decided to give this cast bullet caper a go. having a lot of old shotshell lead that was ballast in a previous life and using a borrowed lee 185 gn mold ,100 donated hornady gas checks and lee liquid alox i was off and runnihg . the powder i had was adi ap 70 n ,i loaded 55 rounds  at 9 grains and increasing every 5 rounds by 5 gn of powder up to 14 grains. after firing and checking each csae for pressure sine i gradually made my way up to 11.5 gns . the result was amazing 1 1/2 group at 50 meters. a local expert wandered by while i was shooting and made comment that i should get 1''or less. so the next week i did the same but this time started at 11 and worked through by 1 gn increments to 12. 11.7 grains was unbelievable 5 shots all touching. so i went and bought a mold and alox and 1000 gas checks. then while trolling ebay one day i discovered free checks and a week later i had one. i went down the same path using up all the supplied shim then move to beer cans but the resultswere just not there .the groups were opening up with more than usual flyers. then quite by accident i came across some brass shim at a local auto parts shop and once again the results amazed me. the bloke at the shop was much amused when i bought 1/2 dozen 6'' square sheets of .006” brass espcially when i told him what i was doing with them..he suggested that i could get it cheeper at one of the bearing and seal suppliers in town. i hit the mother load. 6” wide 10 yrds long $18 australian enough for a very long time. i now shoot the same powder load ,same gas checks in all my 30 cal rifles, the only difference is the lead weight and diameter. i have an israeli mauser in 7.62 that love lee 180 grainers. all my 303s love 185 gn lees and my lastest purchase a mint 1975 top eject winchester 94 carbine shoots 1'' group with 160 grain lee. i did try ed harriss red dot load and got exactly the same results but the australian adi ap70 n is cheaper over here and also works in my martini cadet. i reccomend that anyone interested in cast bullets check out any of ed`stuff on the net and also check out the los angeles sillouette site both are excellent. also dont give up just keep on experimenting i believe that any rifle will shoot with enough time and patience. even worn out martini enfields which doubled as a home for wasps in the barrel and borers in the stock.!!!!

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CB posted this 13 December 2008

Jeff That is one beauty of a target! Those first two are normal for a just cleaned barrel, we call them foulers over here. Those next three are sure pretty. CBA National match caliber for sure! Congrats!

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codarnall posted this 13 December 2008

The genius of the checks working is the experimentation that the user generally demonstrates. Just when I figure a check works at .008” for one casting someone comes along an indicates .006” or say .012".  A spec of a 405 cal. the other day indicated it should be .005” material looking at the shank dimensions.  Jeff demonstrates “fill the bore” as the solution, some have used 3 layers which does seem absurd to me but the proof was the target.

Nice posting and nice targets too!

Charlie

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