310 Cadet

  • 1.1K Views
  • Last Post 03 February 2019
  • Topic Is Solved
tony1960 posted this 19 January 2019

So I've finally gotten hold of the cadet, all the bits and pieces ordered and deliver from the four corners of the globe. So not having loaded for a rifle (loose term) in some 30+ years it was different. Most, well actually ALL of my slow powders are 30+ years old, easily detected by the price marker still on the tin, ah those were the days.

 

I had a small selection of powder that I wanted to try without going out and investing in powder that will only do the same as I already have. Considering that the average charge being 4-9 grains, I have some to last.

Starting with 8gns of Nobels (IMR4227 eqiv) and decreasing down to 4gns of WST (a friends recommendation). Some 125gn 324diam projectiles borrowed whilst my mould arrives, and a learning plane with the strange little case. I load cautiously, only cases with powder go into my loading block.

I was tempted to try some BP loads but the thought of having to clean the gun after turned me off it, the stamp on the barrel shows 310-12-120, who wouldn't be tempted.

I can't get out to the range now until next weekend but with chronograph in hand and 100 rounds to despatch downrange I will post on return.

Attached Files

Order By: Standard | Newest | Votes
barra posted this 03 February 2019

Try wrapping a coke can or other thin hard material shim around the bullet .

Measure that and take away 2x thickness.

Bore diameter is where you spin the bullet in the muzzle and ream away the groves.

should push lightly through the bore but because of a wobble tight spots etc you can have some rifling scratches on the core.

bit rough but better than guess ter mating.

Now if your a professor in maths and have a certifiable veeblock........blahhh blahhh.

you can add the difference between bore and your bore +1 groove to measurement and get a pretty close one too.

Now if you use creasafe then it will shrink a thou or some %.

linotype will expand when cooled.

ww or a blend will be about right.

Now if you could do a pound cast of the throat /rifling origin area with soft lead and the mic it to a feel on the mike you will be a lot closer.

yes I’m bored as you can see and cabin fever is not effecting me at all.

Hadizzy

 

your out of roundness could be acculutadted /lead and crud from gas cutting before the bullet SEAL’s itself against the pressure.

Attached Files

tony1960 posted this 03 February 2019

Barra, just a matter of keep turning until I could fin a point where is was what you would regard as the correct measurement. I knew it was going to be in the vicinity of .320 - .324 so when I couldn't get it bigger than .320 I made an executive decision. So I've been looking at a Accurate Mould 32-125H I may get the heel bumped up to .315 and maybe .321 diam driving bands.

 

Thoughts gentlemen?

 

PS: Stay dry up there Barra, thoughts are with you mate

Attached Files

barra posted this 03 February 2019

How did you measure the 5 groove diameter?

Looks like you are filling the throat which I think is the way to go.

 I reduced my loads after the same primer rubbing with small rifle primers and a sticky shell as I haven’t figured out a way to open the breach if the primer flowed and stuck the case in.

There maybe a way besides bashing the block Down with something like a hammer as  I’ve seen the on other rifles.

Yes mine seems to have large amounts of goop coming out to.

But I believe it is to do with the deep grooves and long barrels.

I tend to favour large amounts of soft lube and soft bullets.

 

Attached Files

  • Liked by
  • tony1960
RicinYakima posted this 03 February 2019

Primers: yep, firing pin hole size (I use that as pressure indicator on mine) and those pistol primers are very soft. I use Federal 100's that do that about 18,000 CUP and Federal 200's at 26,000 CUP. You are doing fine! Ric

Attached Files

  • Liked by
  • tony1960
tony1960 posted this 03 February 2019

So finally made a chamber cast of the little 310, interesting in the fact that maybe I should be thinking about a different diam projectile. Although the gun shoots, boy is it dirty at the end of a session. Liberal amounts of Ed's Red and patches before the bore comes out clean. I can imagine that after close to 100 years of use with varying loads/projectiles that maybe it isn't as pretty in there as it could be. These projectiles are PC'd so this is what I think I am cleaning out of the bore, rather than just a dirty bore.

310 Chamber cast

So what I have found out from measurements:

It has a .320 bore (across the grooves) and .337 at the case mouth. The leade is .323/.324 and in front of the case mouth is a little pitted and out of round but can be expected with a rifle this old, I'll live with it. The rifling starts at 1.315"

My loaded round, unsized case and projectile hand pushed into case mouth, at the case mouth is .336/.3365 OD, projectile diam is .324. My loaded rounds have the ogive end at 1.310.

 

The last couple of thous' is a tight fit by hand and once in the projectile stays there (leade diam), found this out the hard way when I decided to change my mind and ejected a chambered round only to have nearly 5.0 gns of WST casually falling into the action.

BUT the bright side of that was I then learned how to disassemble the action.

I am using Win SPP at present but am finding they are starting to flow at the 1300fps+ mark

My first thought was headspace but the primers aren't backing out, then maybe an excessively large firing pin hole, seems a nice fit so I can only put it down to soft primers. I shall invest in some Small rifle primers and see what happens.

Considering it was a little overcast and 93f with 80%+ humidity as it had been raining that morning, first time in 3 months. My eyes aren't what they used to be especially with such fine little sights I thought the groups were acceptable considering, all 10 shot groups at 50 yds. I was happy with 4.4gns of AS30 (clays). A little sloppy with the 4.8gns of AP70 but still acceptable with a projectile I now know is oversized for this bore.

 

310 cadet + 1 1272.0 4.8 WST 1264.0   1253.0   1255.0   1252.0     Average 1259.2     Standard Deviation 8.6     Mean Average Deviation 7.0

 

 

310 cadet + 1 1280.0       4.8 AP70    1273.0         1274.0         1276.0         1270.0       Average 1274.6       Standard Deviation 3.7       Mean Average Deviation 2.7      

This was also with once fired brass so the lay in the chamber would be different and also the neck tension so I believe this is more of an indicative velocity than previous tests.

 

So now I have a good reason to look at moulds and get one that fits the bore.

Attached Files

  • Liked by
  • JeffinNZ
  • delmarskid
barra posted this 30 January 2019

 

Can’t complain about that for a load.

think I’d keep that one.

Looks like it’s all just dropping in place for you.

You’ll be cleaning up everything thing soon and they’ll resent you for it.

Put gravel down your barrell and nick your crown.

Or maybe just your sights for a bit of a giggle and fix you up some.

 

 I just wonder how accurate these things were when spanking shiny and new.

They seemed to have gotten their poo poo sorted when they made these.

Attached Files

tony1960 posted this 30 January 2019

Well, a "difficult" day at the range, why does it seem that everyone has an opinion as to how you should be doing it, but never having fired or loaded for a cadet. I'm too old to bother listening to the also-rans that they walked away in the end. Every shot fired (100 of them) went over the chrono with some interesting results. 6.0 guns of Blue dot gave me almost 200fps less than it's nearest rival and 7.0 guns of 540 gave the highest with a definite crack at 1400+fps

Standout load: 10 shot group at 50 yds.   5.0 AP70 1324.0 1312.0 1324.0 1312.0 1312.0   AV 1316.8   SD 6.6   MAD 5.8

 I apologise for the less than sharp picture but it looked fine through my eyes wink   Still waiting for the cerosafe for a cast but the fire cases drop back in the chamber and a projectile sits inside the "neck" nicely so won't be sizing at all. It looks like around 1300fps is the sweet spot with this rifle so will put a couple more 1/10ths of a grain in the WST to push it up to 1300fps, I need about 90fps and have a look at the group size.

Attached Files

  • Liked by
  • JeffinNZ
barra posted this 25 January 2019

Just below Cairns.

Try breach seating them with a plugged case sometime.

may or may not make any difference.

Attached Files

tony1960 posted this 21 January 2019

Yes, they are commercial HRBC's, I spoke to Les who I have known for too many years and he gave me the option of two sizes, I went for the larger one as bigger is most often better with cast.

Well, they have all gone into the cases and I checked the first one and on the way through in the chamber as i have been caught before. They all went in with a nice tight feel at the end, action closed with no issues. They should be easier to load after they have been fired, I would have liked to do a chamber cast first but the Cerosafe hasn't arrived yet, that will give me a better indication of what I am dealing with.

I seated the pill just shy of the heel shoulder and it wasn't engraving the projectiles so I may still have a tad to go, once again the chamber cast will tell me that.

Thanks for the offer of cases anyhow, as long as I can get Bertrams I'll be happy for the moment.

What part of this big land are you in, sounds like you should have a surname like "mundi" undecided? Brissy here.

cheers

 

PS: well I've just been downstairs and checked what the max OAL is for this little gun. It seems the longest I can get in there is 1.580", my loaded rounds at present roll in at 1.577".

Attached Files

barra posted this 21 January 2019

What mould have you got or are they the commercial Hawkes?

According to my chamber I doubt you will get the 0.315" heel in the case as the Bertram’s are thick that way. 0.311" seems to be about right.

I use trimmed and thinned 32-20 cases.

It isn’t hard to do thin the rims with a hacksaw blade and a drill just time consuming.

If it needs it.

 I use a Lee case trimmer to shorten them.

I have some Cases I could send if you need some help.

Just keep shortening them till the bullet engraves the rifling and the action closes.

Attached Files

JeffinNZ posted this 21 January 2019

Consider a duplex BP load. I burn 3.7gr AR2205 (H4227 for our US cousins) under 13gr of Swiss 3Fg with a LDPE wad all compressed enough to seat the heel of the bullet. Burns so clean the bore is shiny and I have fired 50 rounds without cleaning and retaining awesome accuracy.

Cheers from New Zealand

Attached Files

  • Liked by
  • Dukem
tony1960 posted this 21 January 2019

Barra, it's AP70 but I do have a couple of kilo's of 50 in the corner somewhere. I might just have to give it a go.

 

My projectiles dimensions are

O.A.L is 17.1mm
Noes diameter is. 318
Driving band is. 323
Heel is. 315
These are weighing on average 126gn

 

I might try to get some BP loads going when I get the cases back, as this is the first firing I'm taking what I get with a pinch of salt, I prefer 2nd or 3rd firings when the case is properly fire formed to get some semblence of accuracy. My cases are Bertrams 310 so no issues with rim thickness or length, they dropped into the chamber.

 

I still have Green Dot, WSF and AS30 (Clays) to fall back on if I'm not happy with what I see. With the amount of info I have read I think I will be on the money though, thanks guys.

 

Attached Files

barra posted this 20 January 2019

If that’s ap 50n then 4 grains works for me.

Attached Files

Dukem posted this 19 January 2019

Black powder cleans so easy, go ahead and be tempted. You will only need to clean the bore on the rifle, and a pull through cleaner will do the job with as little as water on the patch. I like moose milk, then dry patch, followed by Ballistol, but that's just my take. Don't forget to clean the brass though.

Duke

Attached Files

  • Liked by
  • tony1960
Close