Thread: 303 group-bad bedding?

hey people.
Finally got to try out the 303 project. a couple of things to clarify. Using the Greek military ammo from GC, scope a burris 2-10 signature but while I've had it for years, its never been on a gun to try out although it would be a surprise if it was its fault. I'd more suspect the mounts/rings.
Firstly the 4 shot group-this was at 50m-one shot close to centre, second out and up to the right. This was the second group I shot
Okay I think maybe me-third shot close to first then the forth way out again. I must say that no2 and 4 could be around the other way but it doesn't really matter.
This is actually the second group. The first was a bit the same but way worse. I just put that down to me and maybe the barrel needing to settle down after an aggressive cleaning. I didn't post that one.
There is a 3rd shot there but that was me letting my son have a shot from a 303 for the first time and that was pretty close maybe 25m I've seen from comments about tikkas that this is very indicative of recoil lug and bedding. I thought that was two separate groups not pinging back and forwards.
Secondly I was very intrigued by the way the ammo performed. I filled the box up with sand so we could dig the bullets out to show my son.
We put a couple of 243's into there but they just blew up and vanished.
Possibly the fully disintegrated 303 projectiles were from starting at 25 yards, with the others at 50. A couple whizzed across the top of the sand so we didn't get those. Just surprises they blew up so much. The shell for reference didn't go off even after 2 attempts and I swear I had a couple that kicked more than the others and the first group mentioned had one of those.
Thoughts and advice everyone? This rifle hasn't been bedded as I wanted to get an indication how bad the barrel was but I might have to, just to rule it out considering it does put 2 awfully close together-didn't seem like a coincidence
Thoughts everyone?

are the action screws the correct tension???? if they arent a SMLE wont group worth a damn.... you can get 150grn and 180grn soft point ammo ,your rifle will show a distinct liking for one over the other.... having rifle mis fire is really really bad for grouping as it will/can cause you to flinch like no ones business...you dont know if its going to work or not... if you THINK the ammo is inconsistant the rifle will KNOW it is ,rear locking actions like the SMLE are well known for chucking different ammo to different points or impact...if two of the loads were say 2700fps and other two were say 2500fps (you said they kicked different) they would in all probability go to diferent points .in front locking action diference might only be verticle due to speed but with rear locking all bets are off...hope that helps

Got any other .303 ammo to try?

@Micky Duck cheers-This is in a BSA rejigged P14 so not a rear locker. And yes it does help
I didn't read to much into the misfire but as posted when I was finished I did have the feeling a couple kicked more than the others and the very first shot didn't seem to kick much at all really.
If I didn't have two almost touching I'd just say the barrel is fecked. it could still well be it certainly isn't mint.
@Max Headroom no I haven't although it looks like I should just to rule out the first lot.
Strangely enough it seems to get write ups that indicate it should at least show if the rifle shoots ok but with my experience of this lot maybe not.

I’ve found the PPU 150 gr groups well in my No 1 MK 111*, and the cases are great to reload.
Unless the barrel is munted, I’d expect it to group better than the pics.
Did you shoot off a rest ?

Originally Posted by Frogfeatures

I’ve found the PPU 150 gr groups well in my No 1 MK 111*, and the cases are great to reload.
Unless the barrel is munted, I’d expect it to group better than the pics.
Did you shoot off a rest ?

Barrels certainly isn't flash-that cant be ruled out.
Nope not a rest as such-very much rough and ready method. Over the bonnet of the 4wd with padding.
Haven't sighted a centerfires rifle in for years but have done it like this on my other rifles and while I know its not perfect I would expect acceptable results for the distances intended.

If you are going to bed the rifle try Nathan Fosters web site terminal ballistic studies.
He has a section in there on bedding 303 military rifles.
His books are really worth the money and his bedding compound is bloody good. Comes with good instructions and YouTube videos.
Step by step you just need to take your time with it.

Can you put up some photos of the rifle and stock that might be helpful. The target does look like double grouping but other things might fit the bill as well.

try some different ammo. i find mine hates military ammo but likes modern sporting ammo or my relaods.

Splash out on some good ammo, the greek stuff is not really good infact some lots are unreliable. For a rudimentery bedding job use some steel knead it in the recoil lug recess. Wax the action then screw it in tight. It goes off in about 5min.

Originally Posted by Walker

Splash out on some good ammo, the greek stuff is not really good infact some lots are unreliable. For a rudimentery bedding job use some steel knead it in the recoil lug recess. Wax the action then screw it in tight. It goes off in about 5min.

theres a bronze loctite version that is great, i find a thin smear of dishwasher detergent works excellently as a release agent

A lot of worn 303 barrels do not like boat tail bullets. I picked up a tidy PH sporter that was shooting 10" groups at 100 yds with 150 gr. Tried 180 gr Highland (boat tails) 6-8" next, reloads with 180 gr flatbase 4" finally Woodleigh 215 gr flatbase 2.5" groups at 100 yds.

Originally Posted by john m

A lot of worn 303 barrels do not like boat tail bullets. I picked up a tidy PH sporter that was shooting 10" groups at 100 yds with 150 gr. Tried 180 gr Highland (boat tails) 6-8" next, reloads with 180 gr flatbase 4" finally Woodleigh 215 gr flatbase 2.5" groups at 100 yds.

The other factor here is related to weight and boattails: the better grouping ammo types here have the bullet bearing surface increasingly further into the barrel throat when chambered. It may not be the boat tail as such that is to blame - more that a boat tail "costs" you front mass, putting the bearing surface further back, all other things being equal. (a boat tail needs a certain length of cartridge neck to engage with its side to be secure in it, so it needs to be seated deeper).

An engineering workaround the disadvantage of lighter bullets is when Britain replaced the round nose 212 grain Mk V with the 174grain .303 Mk VII spitzer. The Mk VII had a light filler up front which enabled the bullet bearing surface to engage further into the throat of the barrel when chambered. The point of snug/close engagement is that it helps the bullet to travel more concentrically through the bore, thus reducing wobble on exit. The wobble causes the bullet to fly in a spiral path but settles down eventually at some random point in the spiral and flies relatively straight after that - trick is to reduce the wobble in the first place. Imagine if you seat spitzers 1 degree off centre and fire them in a gun with a worn throat... It will make groups shaped like circles with a rare shot in the centre.

If you have a kinetic bullet puller, empty a case for safety and reseat the bullet to its original position, chamber and extract. Pull and reseat to increasing overall cartridge lengths, load and eject, to see how far out the bullet needs to be to engage the rifling lands. Seat your bullets for that gun a bit short of that. This guy here uses a sharpie on the bullets to help read the marks:



But before bothering to do any of this, tighten up and bed the action as advised above. @csmiffy, your groups are not circles, they are being whipped up to the left. You likely have a loose screw.. . (-:

Originally Posted by Cordite

If you have a kinetic bullet puller, empty a case for safety and reseat the bullet to its original position, chamber and extract. Pull and reseat to increasing overall cartridge lengths, load and eject, to see how far out the bullet needs to be to engage the rifling lands. Seat your bullets for that gun a bit short of that. @csmiffy, your groups are not circles, they are being whipped up to the left. You likely have a loose screw.. .

@Cordite good advice-I know about the screw loose-what about the rifle lol
All screws good and tight-I do suspect the bedding and from advice given here, the ammo I have isn't to be trusted.
I don't have a bullet puller but that is something I probably should just get. Or I could put my engineer hat on and make something.
I also think that it isn't just the stability of a boat tail/weight distribution, the theory is more to do with the bum of the projectile not being swaged/obturated against the rifling especially on a worn barrel but good advice still the same.
@Marty Henry I do remember it being the primers as the baddies in the mix for being corrosive-not the powder. I think I will do a bedding job on it. I do need the experience on this project, just was trying not to do it twice.
@shooternz no I haven't slugged the barrel. I was hoping that it might shoot okay with factory ammo and I didn't have to reload at all. in that case 312 is about it.

[QUOTE=csmiffy;750656]I do remember it being the primers as the baddies in the mix for being corrosive-not the powder. I think I will do a bedding job on it. I do need the experience on this project, just was trying not to do it twice.


@csmiffy

Actually, the Cordite was a hot burning powder which by itself caused premature barrel wear, read the history of the Metford rifling. Likewise the contender British powder, Rifleite used by the US Navy in their Lee rifles - same problem. The Metford rifling was not the problem, the propellant was, as evidenced by the Japanese having no problems with their Arisaka Metford rifling but using better, less hot propellant.


As for primers and what's in them, here is a historical progression:U]

Mercury fulminate: 1800s. OK for barrels, but brittling brass, forget reloading. Toxic to eat or inhale. Really bad idea for indoor ranges.

Potassium chlorate: Typical WW1/WW2 primers. Corrosive for barrels and requiring water clean after shooting to prevent corrosion, OK for brass, toxic to lick but not to inhale (OK for indoor ranges).

Lead styphnate: OK for barrels, OK for brass, toxic to inhale - this is the stuff we usually refer to as "non-corrosive primers". Not great for indoor ranges.

You can buy newer compounds - green non-toxic, non-corrosive primers - don't recall what's in them. I'd use only those (or "corrosive" primers) shooting indoors.

I hope this guy is using corrosive primers, or he might get lead poisoning: