No4 barrel bedding sharing

[bow]

Hi you all. i start this thread only for sharing with enfield lovers my shooting experience : today i shot 30 rounds, good cartridges. Trying to obtain the best group i modified my fore end, in a way barrel touch the wood at 12.5 cm from the chamber, for about 2 inches. This is the bedding method explainde in 1991 Canadian Army handbook, you find it at Euroarms Italia. Results : 10 shot groups are at least two time the groups i obtained using traditional approved barrel bedding method. Peter Laidler's words " No one bedding method was found more accurate than the standard approved method" sound in my ears...
Well, my experience is confirming that statement..

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[Frederick303]

Competition shooting would not have adopted the centrally bedded rifle if it was not a good method that provided good groupings with consistent zeros. Having central bed a number of rifles successfully, be aware that a good central bedding is not a simple process. The first thing you have to be aware of is that the upward pressure is rather crucial and will have an effect of the groups. If the pressure is too high and you lift the barrel reinforce off of its bearing you will have poor accuracy (large group). If it is too low you will have all sorts of variable vertical stringing. I have had to mess with the pressure loading at the central bearing on a few rifles to get the best grouping.

I have also seen a difference in the location of the central bed, with three locations being possible, 5.5 inches ahead of the chamber (on the first solid wood area), 7.5 inches ahead (middle of the second lighting cut) the and finally at the middle band 12 inches ahead (under the middle band). In my experience bedding under the middle band is the least advisable, unless you add some packing (aka South African method) to the front barrel bearing surface (normal bedding location). Under this scheme the central bearing is more of a damping bearing then a rigid bearing and needs some sort of flexible material such as graphite/greased cork between the bearing on the wood and the barrel.

Having used the No 4 Mk I and No 4 Mk II in competition (US NRA style) I can tell you that a properly central bedded No 4 is a much better competition rifle then a conventional bedded No 4, due to the fact that the central bedded rifle has much less group shift due to sling pressure. This is true if you use the conventional US single point sling or the British 2-point sling locations. Further once correctly bedded and grouping well, the rifle holds its zero far better over temperature and humidity then a conventionally bedded rifle. I have seen subtle shifts in point of aim between a match tuned front bearing No 4 MK I in winter and summer that one does not see with a centrally bedded No 4.

Be aware I have never fired one of these rifles over 300 yards, so how well the bearing hold up at 600 yards is something I might be wrong about, but the source of my information told me if you get a good grouping at 200 yards with a central bedded rifle it will group equally well at 600, assuming ammunition with normal velocity variations.

[Thunderbox]

Having used the No 4 Mk I and No 4 Mk II in competition (US NRA style) I can tell you that a properly central bedded No 4 is a much better competition rifle then a conventional bedded No 4, due to the fact that the central bedded rifle has much less group shift due to sling pressure. This is true if you use the conventional US single point sling or the British 2-point sling locations. Further once correctly bedded and grouping well, the rifle holds its zero far better over temperature and humidity then a conventionally bedded rifle. I have seen subtle shifts in point of aim between a match tuned front bearing No 4 MK I in winter and summer that one does not see with a centrally bedded No 4.

Be aware I have never fired one of these rifles over 300 yards, so how well the bearing hold up at 600 yards is something I might be wrong about, but the source of my information told me if you get a good grouping at 200 yards with a central bedded rifle it will group equally well at 600, assuming ammunition with normal velocity variations.

Thats really an opinion, not an accurate statement of fact. Many of us find that properly adjusted standard bedding is just as good - certainly at 300 to 1200 yards. I've tested hundreds of No4s, and the majority of the best ones were standard. Centre-bedded rifles have slight statistical advantage in a equal size sample of rifles picked at random - but thats probably just because most of them were built with selected barrels in the first place and had a gunsmith set the bedding, whereas standard No4s have any old barrel and may not have been checked since they were last in service.

I don't think temperature or humidity has much if any effect in most Enfields; they are stocked with seasoned wood and - of course - the barrel heat alone quickly outstrips any environmental effects.

[Frederick303]

Very good point(s) Thunderbox, but I will have to still disagree based on my experience. I have seen No4 of WWII construction that would on a camping trip shift zero over night due to the wet morning conditions. You could feel the difference in the wood based on the spring of the barrel in the front of the wood and in the shift in the shooting. Seasoned wood, but if it is not cut correctly in the first place, it will move with changes in humidity and temp.

Where I live, we have hot humid summers and both periods of cold/ wet, or very cold-dry in winter plus all conditions in between. Getting to matches in summer means having the rifle in a hot trunk at ~100 degrees for a few hours. I maintain very careful log books on each of my shooting rifles and I have seen shifts on more then one rifle, not all WWII make. Of course my rifles shop does not have heat, so perhaps the shifts are more noticeable then someone who keeps their rifles in a house environment.

In any case on a rifle that has that tendency, central bedding is the cure and it works very well indeed, once properly cared out.

By the by, I do not disagree that a conventionally bedded No 4 rifle can be accurate or that if we did a statistical study that it would prove to be on edge slightly better, especially for long range. I think the postings of Capt. Laidler would support the idea that the front bedded rifles gave the best accuracy out of sniper rifles and hence service rifles. I am not denying that.

But the fact remains that the first post simply stated that center bedding made things worse, and by a significant margin. That is simply not so if it is done correctly and if you are using the tight sling approach used in NRA type competition that there are other benefits that folks that shoot off of the bench will not see or understand. A central bedded rifle, done correctly offers a significant reduction in shifts due to pressure points on the forward portion of the forend. Testing rifles in a conventional bench rest or rifle cradle will not illustrate that point, shooting matches will.

If you challenge that point, how do you explain the popularity of center bedding with the Bisley crowd or the cadets?

[bow]

But the fact remains that the first post simply stated that center bedding made things worse, and by a significant margin

I start assuming that if armourers used to do central bedding they had mauch more knowledhe than i have and they di it for good reasons. But ... i checked the correct presure at central bearing , it was 15 pounds, like all enfield experts require.

The groups shot with central bearing were enlarged in vertical, as for low pressure at the central bearing surface.
I'm aware that wood at 5.5" from chamber is thicker, so bearing is more solid, but what i have to do? I obtain the best results with approved bedding method ( 10 shots in 4 cm using military sight at 100 meters) , we shoot with front rest, not a sling. The objective of barrel bearing is tu reduve barrel vibrations, right? To have accurate shots is enough that muzzle points firmly to the center of the target when bullets exit . It's a logical thing the muzzle bearing keeps the muzzle stable when the bullet exit..

[Peter Laidler]

Believe me Bow, Armourers don't do centre bedding - , well certainly those that I know don't. It's the 'gunsmiths' who know best that do that.

Harmonics really is a complicated subject and only those with a degree in music will really understand it BUT, a barrel is really nothing more than a tuning fork............ Just tap it and hear it ring or put a mouthpiece in one end and blow it like a trumpet. On Fred's comments, my sons school Cadet force shooting team rifles were ALL ex No4T's fitted with PH sights and ALL were set up exactly as per the EMER because a) they were Army issued and that's how they had to remain and b) because I used to set them up for them!

Another point to ponder is this............ The actual projectile is no longer influenced by what's going in the bore BEHIND it, it is only influenced by what the barrel is doing AHEAD of it. And if that barrel ain't supported from half way along, then it could be waving around like a spare prixx at a tarts wedding

Here's a little experiment for you all to try to illustrate how much a barrel actually vibrates..........

Get your properly set up rifle with the correct poundage fore-end muzzle weight. Now get a 6" or so length of thin tape - cassette or old reel-to-reel tape is a good start and tie a 1/2" or so nut to one end. Lift the barrel up and push 3" or so of the other end into and under the barrel so that when you release the barrel the tape is gripped firmly between the flexible barrel and fore-end. Put the rifle on the shooting bench so that the tape and nut are hanging free but gripped between the barrel and the fore-end.

Fire one round at the target and you'll see that the barrel vibrates or whips to the extent that the tape is released and under the weight of the nut, will fall to the floor.

Obviously we used to do this on an Enfield rest in controlled conditions but it shows just how much the barrel lifts/vibrates/whips. Now if it does this when the barrel is supported (it is technically 'damped') at the muzzle, just ask yourself what it'll be doing when it's undamped

[Son]

Another thing that has gone unasked as yet... Bow, what ammunition are you using?

saw a funny (as in stupid) comment on a forum the other day where a certain bird starting with T said he had never experienced wandering zero with his No5 and more or less chalked it off as a myth, then next post tells of using only 150gn pills and light loads so he can get maximum life from his brass.

[bow]

I use factory Sellier&Bellot ammo, 180 grains FMJ for training. These cartridges gave me consistent 10 shot group ander 4 cm. at 100 meters with iron sight and 13 cm at 300 cm. For competitions i reload my ammo using N140 or IMR 4064 and Sierra Match King bullets. Groups are just a few smaller , imr 4064 give me lower velocity spread. It's impressive the accuarcy level this old work horse could offer!

[bow]

Thanks Peter. You gave us a practical method to see barrel vibrations

[RobD]

If you are getting <4 cm 10 shot groups at 100m with a No 4 ... then you are doing reasonably well... in my humble opinion...