No4 Scope mount holes misaligned and drilled too deep?

Just went to try a Parker Hale BA20 on my Savage No4 which appeared to have been drilled for this type of mount. Firstly, the two holes are not in alignment, second the threads differ from those of the supplied screws and third and more worrying, the holes seem to have been drilled right through the receiver and into the top of the barrel threads.
Can anyone advise on how deep these holes should be and why they might have been drilled askew or does this just sound like a DIY gunsmithing job.

Please note that I'm a novice so perhaps all is OK and I am expecting too much more precision.

It seems to me that someone has tried to drill the holes originally and failed....., then sold the rifle on.

Can I make a suggestion? It's this. The sheer notion that you can screw a telescope front sight base to a No4 receiver ring and expect it to remain tight and soliud is the stuff of fairy tales. It ignores the basic schoolboy physics of rotational forces that you learned in your first year physics lessons at school. You know, clock and anti clockwise moments and all that stuff............... And whoever thought that small BA (or close to....) threads going into 3mm or so of mild steel revceiver ring would be sufficient to hold firm was living on another orbitory planet to the rest of the world. My suggestion is to ignore these holes, give the blocks you've just acquired away to someone you don't like as fishing weights and get a steel one piee easily mounted bracket to fit onto your rifle.

You were/are right. These blocks are an amateur DIY gunsmiths job

Quote:

---

Originally Posted by Peter Laidler

It seems to me that someone has tried to drill the holes originally and failed....., then sold the rifle on.

---

Thanks for the reply.
I thought it looked a bit of a weak solution but gave it a try as it looked cheap, quick and easy.
This rifle has been reported on the Web as having 2-5 MOA accuracy so I thought a scope might help.
I will stick to the standard sights for now.

I seem to have a habit of collecting "sold on" rifles so far!.
How do novices avoid buying all the "sold on" rifles?.

Or just get one of those steel single one piece mounts from that firm based at Bisley. Those are as good as it gets.

Quote:

---

Originally Posted by Peter Laidler

It seems to me that someone has tried to drill the holes originally and failed....., then sold the rifle on.

Can I make a suggestion? It's this. The sheer notion that you can screw a telescope front sight base to a No4 receiver ring and expect it to remain tight and soliud is the stuff of fairy tales. It ignores the basic schoolboy physics of rotational forces that you learned in your first year physics lessons at school. You know, clock and anti clockwise moments and all that stuff............... And whoever thought that small BA (or close to....) threads going into 3mm or so of mild steel revceiver ring would be sufficient to hold firm was living on another orbitory planet to the rest of the world. My suggestion is to ignore these holes, give the blocks you've just acquired away to someone you don't like as fishing weights and get a steel one piee easily mounted bracket to fit onto your rifle.

You were/are right. These blocks are an amateur DIY gunsmiths job

---

A little harsh dont you think !
With a 'military' hat on, and knowing the rifle is going to get knocked about, mistreated and generally unloved you may well be correct, however there are many hundreds / thousands of No4 based Enfields that have succesfully used the BA20 / 21 scope mounts (including the Police Marksman Enforcer) with (apparently) no complaints.
The Enforcers I have had have been rock solid with no sign of movement of the scope mounts.

I just KNEW that you'd come back Alan and others and I know it was a bit harsh............ but......... as JSS was (virtually) starting from scratch, It'd be better to start with a V-W solution than a British Leyland solution. After I'd written it, I thought that I SHOULD have said afterwards something like '..... head down, steel helmet on......INCOMING!' I've spent a couple of days reading old trial reports and one that I havce been reading relates to the Enforcer rifle that was subject to some trials by the MoD. I'd be sued if I told you what they said about the PECAR telescope. It effectively said that it and the rifle might be alright for any non robust handling but as a snipers telescope, they'd stick with the other contender, a Tasco (I've never heard of a Tasco but I'm not aware of the commercial world). Admittedly, they didn't parachute container drop them during the trials as they did with the No4T's, L42's L1A1 rifles's S&B, Leatherman and the like.

We also seem to forget that there were many instances where the front blocks were drilled right into the barrels so far in fact, that the fired cases bulged into where the chamber was weakened by the 2x screw holes. Enfield said it wasn't them (naturally) and the civvy gunsmiths who had to deal with the loose pads afterwards said it wasn't them who'd drilled and tapped the holes deeper so as to create a more substantial screwed bond.

It's just an engineering fact that a 3mm (? I haven't got one handy here to accurately measure....if someone can do it for us. From thread root to O.D. of the receiver) is insufficient or at best, marginal thread depth. You can lock it down as much as you like. You can use HT allen bolts but it's STILL 3mm or so of what is effectively mild steel - albeit good quality mild steel.

This could be an interesting thread Al...........

Quote:

---

Originally Posted by Alan de Enfield

A little harsh dont you think !
With a 'military' hat on, and knowing the rifle is going to get knocked about, mistreated and generally unloved you may well be correct, however there are many hundreds / thousands of No4 based Enfields that have succesfully used the BA20 / 21 scope mounts (including the Police Marksman Enforcer) with (apparently) no complaints.
The Enforcers I have had have been rock solid with no sign of movement of the scope mounts.

---

Yes, the mounts work perfectly well on Enfield conversions. Virtually identical PH mounts - using the same short grub screws - were used on much bigger calibre sporting rifles based on Mauser actions. I guess the strength really depends upon the weight of the scope/rings, and also the quality of the initial drilling & tapping. Many rifles have the screws loctite'd in, and they can grip very tight indeed. You do see a lot of DIY butchery with these mounts though....

---------- Post added at 07:34 PM ---------- Previous post was at 07:27 PM ----------

Quote:

---

Originally Posted by Peter Laidler

I'd be sued if I told you what they said about the PECAR telescope. It effectively said that it and the rifle might be alright for any non robust handling but as a snipers telescope, they'd stick with the other contender, a Tasco

---

The strangest thing about the choice of the Pecar is that the scope length and eye relief - when fitted to an Enfield - make it almost impossible for most normal people (incoming!) to hold the rifle in a good firm shooting position. You have to hold your head right back at an un-natural angle to get the correct scope picture, or align your body in line in order to achieve the same. I've often wondered if that why they put the Harris bipod on the Enforcer - so that you can take a Bren/GPMG type of hold on the rifle instead...

It's funny that you mention the Harris Bipod because that's mentioned too! I'll have to get it all out again........................... I wish I hadn't started now!

Quote:

---

Originally Posted by Peter Laidler

'..... head down, steel helmet on......INCOMING!'

---

Oh dear, which forum do I get my steel helmet from?.

I still feel that the BA20 looks as if it needs at least beddng on Araldite or something, and the screws just don't look man enough, although they might just do the job with loctite.
I will try it on my No4 MkII which is correctly drilled and tapped.
Could anyone advise on suitable scope and mounts for the BA20/21 combination to give lowest line of sight in order to avoid adding a cheekpiece on a No4.
I will also try the steel "no gunsmithing" option from bisley on the savage/sterling 7.62.
Thanks again for the interest and input.

Quote:

---

Originally Posted by Thunderbox

The strangest thing about the choice of the Pecar is that the scope length and eye relief - when fitted to an Enfield - make it almost impossible for most normal people (incoming!) to hold the rifle in a good firm shooting position. You have to hold your head right back at an un-natural angle to get the correct scope picture, or align your body in line in order to achieve the same. I've often wondered if that why they put the Harris bipod on the Enforcer - so that you can take a Bren/GPMG type of hold on the rifle instead...

---

So True - thank God for that, I thought I was abnormal, but I must be normal as I have the same problem.

Quote:

---

Originally Posted by jss

Could anyone advise on suitable scope and mounts for the BA20/21 combination to give lowest line of sight in order to avoid adding a cheekpiece on a No4.

---

Parker Hale mounts and a straight-tube scope. There is a whole thread about faux sniper scopes, and most of those scopes mentioned are a good choice.

Quote:

---

Originally Posted by Peter Laidler

The sheer notion that you can screw a telescope front sight base to a No4 receiver ring and expect it to remain tight and soliud is the stuff of fairy tales. It ignores the basic schoolboy physics of rotational forces that you learned in your first year physics lessons at school. You know, clock and anti clockwise moments and all that stuff

---

Even more intriguing to me than the mounting stability is the affect of the deflection of the action upon firing would have on a well clamped scope tube over a fair number of cycles. The No.32 bracket's rear contact surfaces have some built in fore and aft "slippage" and it's robust construction would prevent transference of most strain to the scope tube proper.

BTW, it's more than a purely theoretical concern, I've seen more than one commercial scope that's failed through it's turret! (One piece designs-not so much, but I THINK Pecar tubes are assembled to the turret like most of the time period.)

There is no in built 'slippage' with the No32 bracket JM because the bracket is fixed onto the dowel-like spigot on the front pad. So fore and aft movement is limited to NIL! Just a small point because it is the front spigot and rear dovetail that ensure that the sight will always correctly re-align on reassembly. We had a wall chart to test for this.

Incidentally, the front spigots could and did shear off during recoil but there was a repair procedure in place. The spigot had to be a stonking good fit (that's another REME technical phrase for PERFECT mechanical fit) into the corresponding hole in the bracket.

Pete, nothing wrong with he Leyland P76 collectors item now, you woulld have to trade an enforcer, maybe two now for a good one.

Myles

Go on, what's a Leyland P-76? That's not the Rover 3.5 litre that the poms called the SD-1 is it. When I was in Australia, we thought that BMC (for British Motor Corporation) stood for bloody mooka crap. Happy days............. I saw Rockhampton mentioned in the recent flooding and thought to myself, after having spent many weeks there and Canungra, that it couldn't have happened to a nicer place

Quote:

---

Originally Posted by Peter Laidler

There is no in built 'slippage' with the No32 bracket JM because the bracket is fixed onto the dowel-like spigot on the front pad. So fore and aft movement is limited to NIL! Just a small point because it is the front spigot and rear dovetail that ensure that the sight will always correctly re-align on reassembly. We had a wall chart to test for this. Incidentally, the front spigots could and did shear off during recoil but there was a repair procedure in place.

---

I reckoned that the rear dovetail might slide fore and aft a few thousandths under recoil, but return when the load was removed. However, if the rear is locked from movement (dang, I can think of a fairly simple hydraulic test stand w/ a dial indicator that could test it, IF I could afford to potentially tear up a rifle!!) it would load the front spigot- leading to possible eventual shear failure...

Quote:

---

I saw Rockhampton mentioned in the recent flooding and thought to myself, after having spent many weeks there and Canungra, that it couldn't have happened to a nicer place

---

:lol::lol::lol:

Quote:

---

Originally Posted by BushyFromOz

:lol::lol::lol:

---

No4 scope mounting to Aussie Leyland P76???. :madsmile:
The P76 was indeed a great tool for towing a 3 ton yacht down to Scarborough marina!. Shame about the sharks and sandbanks in Moreton bay though!.:yikes:

Quote:

---

Originally Posted by Alan de Enfield

So True - thank God for that, I thought I was abnormal, but I must be normal as I have the same problem.

---

You and me both, Alan. Every time I shot the blooming thing, I'd get a crick in my neck, and that isn't good for a chiropractor....

I think I'll save my pennies for an L42A1 (who am I kidding....)

I agree with Peter: a Mickey Mouse setup if ever there was one. However, if you get the steel bases, not the laughable pot metal ones, and solder the front base onto the barrel ring, and solder the screws in too, you're as well set as most other cheap commercial scope mounts.

Collimation? Forget it. Zero at one range and be thankful for that!

Quote:

---

Originally Posted by Peter Laidler

And whoever thought that small BA (or close to....) threads going into 3mm or so of mild steel revceiver ring would be sufficient to hold firm was living on another orbitory planet to the rest of the world.

---

Well I think that this statement is absurd!

Let’s think of a Parker Hale L82 (C3) sniper rifle, their mount has 4 very small bolts that are attached to the receiver which is 3mm thick!!
So peter are you saying that these rifles are badly engineered (I don’t think so) they give suburb service to Australia, New Zealand and Canada.

I do agree about the Pecar scope the ZF69 was the pick of the lot.

'So peter are you saying that these rifles are badly engineered........' . No. The rifles were perfect. In fact the P-H constantly beat the AI L96 for accuracy. Am I saying that the telescope mounting was badly engineered. Speaking as an engineer and someone who's been in the Military small arms system for a tad over a year or so, then I'd say that the tele mounting system used on the Enforcer wasn't just badly engineered, I'd say that it went beyond that. I don't know enough about the mechanics (receiver ring thickness etc) of the PH fitting to comment. But I DO know a few things about the Enfield

Here in NZ there were hundreds of Enfield’s that were used for deer recovery fitted with the PH top mount and a scope that is attached in the manner discussed here, these rifles were very poorly handled & treated I would go so far as to say way worse than in the military as another rifle cost very little if the rifle was lost or dropped out of a chopper etc, none of these rifles suffered any problems with their PH mounts or how they were attached and indeed there are still loads of these rifles still in NZ giving good service to this day after years of abuse with this mount this must count for some thing?

The UK MoD could have adopted a 'new- build' L39 enforcer type sniper instead of the L42 but the trials dictated that it wasn't robust enough. Likewise, during the 80's we could have adopted the more accurate (than the L96) PH sniper rifle. virtually off-the-shelf on the basis of the Can; NZ and Aust. experience but once again, it wasn't robust enough for what a sniper rifle needed to be. It had to be a readily take-off mount for the telescope among other things.

I feel the urge to repeat the process of trials that took place between the contenders but I don't think it will be possible/allowable. But suffice it to say, those mounts didn't get past the first hurdle for a sniper rifle. It's ironic that in the midst of this, the 3 nations have now adopted the L96 or variations of it. And I know for certain the Australia did solely on the basis and say so of our Warminster trials

As I always say..........., You cannot even compare sniping with other forms of shooting. There's a world of difference between the different and various sporting rifles. But sniping is the only sport where the quarry shoots back.

I know it's being a bit pedantic Chris, but are you sure that NONE of these hunters rifles suffered any problems? Surely one or two might have...!

Quote:

---

Originally Posted by jss

and third and more worrying, the holes seem to have been drilled right through the receiver and into the top of the barrel threads

---

Quite right to be worried. In Mauserland the rifle would be viewed as unsafe by a proof house. My local dealer showed me a Mauser where Bubba had done just that. The proof house refused to accept it for proof firing. Then he had welded up the holes, and presented it again. Bubba now has an officially condemned wall-hanger.

:wave:

Quote:

---

Originally Posted by Patrick Chadwick

Quite right to be worried. In Mauserland the rifle would be viewed as unsafe by a proof house. My local dealer showed me a Mauser where Bubba had done just that. The proof house refused to accept it for proof firing. Then he had welded up the holes, and presented it again. Bubba now has an officially condemned wall-hanger.

:wave:

---

Its quite common to find PH BA20 mounts where someone has replaced the short screws with much longer ones, and the holes have been drilled down through the breech ring into the barrel itself. I've never heard of one of these rifles failing UK proof, as the proof houses are not into the business of dismantling rifles to check scope mounts, etc. Only if there is a noticeable incident with the proof cartridge will the rifle be examined. The holes have to be practically through the chamber wall before anything much happens. I have heard of one or two rifles where the mount holes were so deep that fired cases ended up dimpled as the chamber wall had subsided a fraction over the holes.

I'm sitting firmly on the fence here as my limited knowledge is really limited to the military aspects of firearms. BUT........., ahem......, on the basis that 'people' do indeed drill into the barrel (ouch!) to mount these pads more securely then surely it'd be better if they just drilled in to a much shallower depth and used a more substantial, say a 0 or 2 BA ish dia screw. I'm thinking tooth root strength and all that engineering stuff.

But I think we're all agreed that drilling into a barrel is what I'd call in technical language 'p--s poor engineering practice'

When the holes go into the chamber, it seems that the cases will blank out discs into the hole until the last one won't quite clear, and the case doesn't want to extract. (Saw this once.) The other thing that I've seen is that the poorly threaded hole won't retain the screw, and it pops up until it won't go further. (Saw the remains of a couple of those, after the fact, in a junk pile.)

USUALLY, nothing happens because the driller has a clue or a conscience (generally not both!) and the barrel is scrapped.

There is the rare instance where the perpetrator has caught his mistake, run a set screw into the hole, dressed off the bottom flush in the chamber, and continued on mounting the scope. Haven't seen it myself, but it was related to me by one of the 'smiths that "trained" me many moons ago.