5.6x57 development

[Waldo]

I got out out bed fairly early this morning as I'm looking after the young fella for most of today and trying to watch the bike GP on TV at the same time, mmmm may get a bit awkward.

Anyway I finished prepping some brass and split a case neck with the dremel to test distance to lands with the 75g Amax. I came up with a distance of 3.002" to the lands so knocked about 20 thou off that to come up with a COAL of 2.980", loaded up a dummy and it still looked a little long so settled on 2.975" for starters.

Here's the dummy round, looks pretty impressive next to a factory FMJ round.


Purchase of the non boat tail section of the projectile comes in at .192" which indicates it could go in a little deeper, I haven't set the die up to crimp but even with a split neck it still takes a couple of decent taps with the bullet puller so it has a pretty good hold anyway so I don't think it is necessary?

If I get a chance late this arvo I'll see if I can run a few loads together to test over the chrony next weekend, should be interesting.

Cheers,
Waldo

[Waldo]

I got out just before sun up this morning to tag a few roos this morning (under permit of course), put the 5.6x57 and a bunch of hand loads in the ute to throw over the chrono if I got the chance.

I had loaded up 2 of each starting at 34.5g then 0.5 grain increments til 37.0g then 37.2 and 37.4g. First over the chrono was the factory loaded FMJ's and these went 3366/3371fps so are zipping along pretty well.

The 75g Amax's went as follows:
34.5g: 2945/2949
35.0g: 2957/2962
35.5g: 3099/2960
36.0g: 3028/3037
36.5g: 3100/3033
37.0g: 3210/3127
37.2g: 3148/3093
37.4g: 3215/3198

Interesting results in regards to velocity variation with lower charges with minimal variation then it opens up a bit with the 37.4g load starting to come back again. Thankfully the primer issues with the factory KP's has disappeared with the reloads so all good there. No pressure signs so I'll sneak up a little higher and see how it goes at the range next time, if I can get another 100fps and it shoots like stink I'll be pretty happy

Cheers,
Waldo

[MISSED]

Interesting results Waldo and by the looks you will be able to go a bit higher in the charge rates.

[Waldo]

Interesting results Waldo and by the looks you will be able to go a bit higher in the charge rates.

Yeh, 37.4g will be my new starting load so I'll give em a bit more go juice and see how they go on paper, it was handy to get a starting point though.

[Camel]

Good going mate, its interesting watching how this saga is going along. Thanks for keeping it up to date. Didn't notice which powder you are using ??? Looking at the comparison photo between the two cases, it really shows up how thick the brass is in the neck of the 5.7x57.

[Waldo]

2209 is providing the KABOOM bit.

Yeh, its been a bit of a saga and while frustrating at times I've enjoyed working thru it bit by bit. Gotta admit after the primer issues I was a bit tentative when I pulled the trigger on it this morning, mighty relieved that everything was OK and continued to be OK as I worked my way up the powder loads.

I'll load up a few rounds tomorrow if I get a chance, hope to have it sorted and sighted in for the Amax by the time I go and dong a few more roos on the head (still got close to 30+ tags to fill). Hopefully the grass will flatten off a bit by then, the waist or higher grass made it tough to get a good shot this morning.

Stay tuned I'll report back after the 5.6 has a range visit

Cheers,
Waldo

[Waldo]

Well that was a couple of frustrating hours in the shed. I grabbed a RCBS shell holder during the week as I was having some issues with some of the cases not fitting into the Lee shell holder and the random 3 cases that I thru in my pocket all fitted into the RCBS version at the LGS, all good I hoped.

Well I started setting up the die for the new shell holder and after a bit of stuffing around was happy where I was as my test shell was looking and feeding OK so off I go and deprime/resize a few cases. All was going good till I decided I should check a few randoms to make sure everything was OK. I'll be buggered the first couple wouldn't let the bolt close, run em thru the die again and same result, ended up with 11 out of 25 that didn't feed, ggrrrr.

Fart arsed around a bit more and started taking some measurements and the offending cases are about 20thou longer to the shoulder. Only thing I can think it may be a bit of flex in the press? It's a lower end Lee press that I initially brought just to use a FCD for the 45/70 but ended up liking the Lee stuff a lot so switched over from the old SImplex press I was using.

Gotta admit this cartridge has been proving to be a bit of problem child, gonna be sweet when I eventually get to shoot something with it.

Oh yeah still have a few cases that won't fit in the RCBS shell holder too ggrrrrr.

I was going to revert back to the Lee shell holder and try re-sizing them and see how they went but gave up and packed it away instead,another day.

FLS just doesn't seem to working for me on this one, anyone out there using a universal neck sizing die?

Cheers,
Waldo

[Tackleberry]

when the ram is all the way up get down and have a look and see if there is any clearance between

the shell holder and the fl die with the case in, i bet there is it even happens with a RCBS rock chucker .

just keep screwing the die down a 16th of a turn until the shell holder and die touch

under pressure .

if the press cracks it cracks

[Camel]

Stick with it Waldo, with the troubles that you have had with this one, you deserve a break and its bound to be a good shooter.

[Waldo]

Well I couldn't leave it like I did it would annoy the crap out of me all week.
I wound down the die and kept on going till it worked, ended up 3/4 turn down and put all my weight on the handle. Fed all 25 thru the rifle and just had 2 a bit snug so gave them another go.

May be about time to upgrade the press for something a bit more heavy duty.

Cheers
Waldo

[Waldo]

Just been pondering the next step, last weekend I prepped 22 pieces of brass (yeh, a bit of an odd number but it just happened that way). The 37.4g was humming over the chrono at around 3200fps and I'm keen to get up into the mid-high 3300's so I was looking at loading up:
37.4g x 4
37.6 x 6
37.8 x 6
38.0 x 6

I'll shoot a group of the 37.4's to see how it goes then 2 of each load over the chrono (yeh, I know a small sample) and a 4 shot group (well 3 shot group plus a flyer more than likely ) Hopeful of getting all the way to the 38g load without pressure and seeing what this unit can do, if I can get to 38g it should be pretty impressive.

This is the first time I've ever developed a load using a chrono and first time I've ever bothered pushing above max. listed loads, interesting stuff?

Cheers,
Waldo

[Camel]

So this is still using the 75 gn Amax ??
Just went and grabbed uncle Nicks second edition (only one I have) but it doesn't go past 60gners and is pre most ADI powders, so cant help you there. The ADI fifth edition from 2010 I have lists 74gn bullets, doesn't say which, with 37gns of 2209 as max. I wonder if there would be any advantage of trying 2213sc, just because ????? Nice big case and if you have a nice long barrel it may be worth a try.

Just checked the 6mm Rem, they list a start load of 48.0 of 2213sc with 75 gn bullets as a start load at 3210fps, with a max load of 51gn for 3490 fps. I know you cant directly change data between different calibres, but it gives room for thought.

[Waldo]

Yep still the 75g Amax. I only really picked the Amax because it seems to have a good rep for being an accurate pill. Once I have it shooting well I may test a couple of more hunting orientated pills and see what it does with them.

Load data floating around with a 75g .224 pill is a bit scarce on the ground. ADI online lists the 37g g 2209 with the 74g'er, the 37.4g load is still 50fps behind their supposed 37g load of 3250fps (still heaps of space in that case too).

I would assume the 74g data is based around the RWS konepoint 74g'er?

I have read on some sources that 220 Swift data comes close as case volume is similar (it's on the net so it must be true, right ) ADI for the swift list a 70g'er at max 38g 2209 for 3313fps, also have AR2213C for 42g for 3359fps so you may be onto something with the 2213.

Either way I've still got a bit to go it seems, soon find out.

If the 75g'er's don't so it for me I have some 69g (Sierra's I think) in the cupboard to try also. If I get really desperate I'll throw some 45g ACP's in them, they should really get up and boogie

Going to the rifle range generally doesn't over excite me much (rather go hunting) but looking forward to getting this thing set up nicely, I think it has some potential.

Cheers,
Waldo

[Waldo]

I loaded up a 1/2 dozen rounds this morning, 2 each of 37.6g, 37.8g and 38.0g. Snuck out and put em over the chrono and still seem to be getting some quite large variances in velocity. After the first of the 37.8g loads blew off one of the sun screens I pushed the chrono back a bit further so perhaps that was my problem, still learning on that one as a new chrono owner/user.

Anyway here's the results:
37.6g 3130/3197
37.8g: 3299/3138
38.0g: 3248/3285

Even after moving the chrono further out for the 38.0g loads variation was still a bit higher than I would have expected?

Anyway, here's a couple of pics:
Kinda shows how much brass is in these things:


The last of the 38g loads motoring along OK:


I'll load a few more up today then see how it goes on paper tomorrow.

Cheers,
Waldo

[aaronraad]

The last of the 38g loads motoring along OK:


I'll load a few more up today then see how it goes on paper tomorrow.

Cheers,
Waldo

Shooting Chrony obviously understood the frustration that sometime comes with load development and added the "FU" button in the top left corner.

Did you ever establish if the 75gr Amax's were meant to be stabilise in your barrel twist at those velocities and atmospheric conditions?