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Sako3006
26-03-2012, 22:16
Hi guys
I am not sure if this one has been covered before so please bear with me.
I have recently got hold of what I believe is a BSA Hunter 7x57 serial no C5Bxxxx. I am having a go at restoring the rifle as the barrel is in excellent condition. I currently have it stripped down and am dealing with the wood work. However the Trigger most certainly needs setting up and I hope someone can advise me on the best proceedure. The trigger is a wide(ish) ribbed blade with a grub screw at the front, also one in the centre of the blade which would sit above the finger position and one behind the trigger blade (though set in the trigger blade)
The pull is like a two stage and heavy, though crisp and the trigger mechanism would appear clean and in good order.
Any help would be much appreciated

Brithunter
27-03-2012, 01:09
OK this is from John Knibbs book:-


The newlt designed trigger mechanism consisted basically of four major components, trigger, trigger pawl, sear trip, and sear. These, together with their operating springs were contained within a seperate pressed steel housing which was fitted to the receiver by menas of a front screw and rear pin. Hinged together the the sear was the ejector which was spring loaded and which rose up and contacted the cartridge head on the final rearwards movement of the bolt. The sear also doubled as a bolt stop engaging in a shallow depression in the underside of the bolt preventing complete withdrawal when the bolt was fully opened.

The let-off weight of the trigger could be adjusted by means of a screw set in the front of the trigger blade. The top of the trigger housed a second screw which controlled the creep or movement of the trigger; adjustment of this screw was sufficient to give a double pull action if required.

He does not mention the third screw at the rear of the unit. The rear screw if memory serves me correctly is the sear engagement so care should be taken when adjusting it. Adjust it too far and you will not be able to get the bolt out without removing the trigger unit. Also from memory I don't think it's designed to go much lower in pull weight than about 3lbs maybe 4 lbs. Back in 1952 this was considered light for a sporting/hunting rifles trigger.

Now due tot eh rifles age may I suggest you look carefully at teh sears engagement surface where it catches the strikers cocking piece for wear and burrs. If these are not clean and smooth it will effect the trigger pull. Once these are smooth and burr free then one can adjust the trigger.

Now I have found that leaving a tiny bit of first stage pull gives a cleaner let off. Adjusting the unit to single stage only seems to leave some creep however this is effected by the amount of wear in the trigger unit itself. My Regent in .222 Rem has a very nice crisp trigger as does the 59 Vintage Majestic Feather weight. A 1960 vintage Majestic is not quit as good probably due to a bit of wear?

Hope that is of some help to you.

brenneke
27-03-2012, 01:39
Sako, i am currently waiting on my paperwork to come through so i can take possession of my Hunter/Viscount - which is in 243 (i am envious of you finding a 7x57!). If you get the chance, do you mind measuring your maximum magazine length for me? I am expecting to rebarrel, and am thinking i might start that process whilst waiting for the rifle, and am trying to decide on a cartridge.

Brithunter
27-03-2012, 01:53
Sako, i am currently waiting on my paperwork to come through so i can take possession of my Hunter/Viscount - which is in 243 (i am envious of you finding a 7x57!). If you get the chance, do you mind measuring your maximum magazine length for me? I am expecting to rebarrel, and am thinking i might start that process whilst waiting for the rifle, and am trying to decide on a cartridge.

It's not the magazine which limits the length but the position of the machined bolt stop on the underside of the bolt. If you rifle is a .243 then it will have the bolt stop machined into the bolt underside for the length of the .243 cartridge.

brenneke
27-03-2012, 02:11
Yep, but i am figuring as it is a short action the magazine and bolt--stop will be the same for both actions. But, yep i take your point - i could be wrong and find it is shorter (i am aware BSA did this with subsequent designs). I will have a look at the barrel first, any way. It may be better than i expect - i was told it looked almost pristine, but it is a couple of thousand kilometres away and never trust what i am told on the phone!

Brithunter
27-03-2012, 08:47
Yep, but i am figuring as it is a short action the magazine and bolt--stop will be the same for both actions. But, yep i take your point - i could be wrong and find it is shorter (i am aware BSA did this with subsequent designs). I will have a look at the barrel first, any way. It may be better than i expect - i was told it looked almost pristine, but it is a couple of thousand kilometres away and never trust what i am told on the phone!

May I suggest that you carefully and well and truly clean the bore before making judgements on it. The reason I say this is that I purchased a Majestic Featherweight in 270 Win with what looked like a very poor worn bore. It was priced accordingly and had sat on the dealers rack then in a back area storage for years due to this.

On getting it home I gave it a clean then shot it as one normally does. I then cleaned it again as it was supposed to be the donor for my .280 project. When I cleaned it it was still slightly warm because I shot it on our field and the crud the P-H 009 shifted made me look closer.

So I set about "Really" cleaning the bore. It took me abut two and a half days of alternate use of P-H 009 nitro solvent then after a good wiping out an application of Forest Foaming Bore cleaner to attack and remove the jacket fouling. The P-H 009 was left to soak f0r at least half an hour and sometimes longer. It was left in with rifle standing muzzle down over night and the paper it stood on was blue stained in the morning. I doubt the bore had ever been cleaned properly in it's 50+ years.

By the time I had finished the rifling was about double the depth it was when I picked it up and suddenly it looked like it should. Sure there is a little rounding on the lands due to wear but it shoots MOA with some Federal Factory 150 grain ammo easily. So the 1st pattern Monarch who's bore was more worn got used as the donor.

I can see this sort of thing being more common with the huge sales and usage of bore snakes.

dingwall_dave
27-03-2012, 09:22
OK this is from John Knibbs book:-



He does not mention the third screw at the rear of the unit. The rear screw if memory serves me correctly is the sear engagement so care should be taken when adjusting it. Adjust it too far and you will not be able to get the bolt out without removing the trigger unit. Also from memory I don't think it's designed to go much lower in pull weight than about 3lbs maybe 4 lbs. Back in 1952 this was considered light for a sporting/hunting rifles trigger.

Now due tot eh rifles age may I suggest you look carefully at teh sears engagement surface where it catches the strikers cocking piece for wear and burrs. If these are not clean and smooth it will effect the trigger pull. Once these are smooth and burr free then one can adjust the trigger.

Now I have found that leaving a tiny bit of first stage pull gives a cleaner let off. Adjusting the unit to single stage only seems to leave some creep however this is effected by the amount of wear in the trigger unit itself. My Regent in .222 Rem has a very nice crisp trigger as does the 59 Vintage Majestic Feather weight. A 1960 vintage Majestic is not quit as good probably due to a bit of wear?

Hope that is of some help to you.

Has anyone got a diagram for this? I prefer a two stage trigger, and quite fancy setting my .270 Monarch for that. Being an engineer of sorts, I work better with pictures...

Brithunter
27-03-2012, 17:12
Sorry old chap but hate to burst your bubble butt he Monarch has got a cheapened version of the Hunters trigger with only two adjustment screws:-

http://img.photobucket.com/albums/v166/Brithunter/BSA Monarch 1st pat/P4200057.jpg

http://img.photobucket.com/albums/v166/Brithunter/BSA Monarch 1st pat/P4200058.jpg

http://img.photobucket.com/albums/v166/Brithunter/BSA Monarch 1st pat/P4200056.jpg

The trigger from a 1st Pattern Monarch.

Note the much wider blade. It's almost twice the width of the Hunter and Majestic trigger blade. I cannot recall and I cannto check if the Monrach trigger can be made to have a two stage pull or not ............................... sorry.

Oh yes 2nd pattern Monarch has a different trigger again.

dingwall_dave
27-03-2012, 17:37
Curses. Foiled again.

Cheers Brit, saves me making an arse of things trying.

Brithunter
27-03-2012, 18:29
I cannot access my rifles but you can yours so try adjusting the two screw on yours carefully. The one in the blade in the pull weight the one at the rear is the sear engagement which might also effect the over travel.. Again I cannot remember because it wa s along time back that I adjusted those that needed is.

Sako3006
27-03-2012, 19:45
Thanks Chaps the information you have supplied is very helpful indeed. Thanks Brit inparticular for your valued input.
Brenneke no problem the magazine box (internal measurement) is 3-3/8" or 80mm hope that is of help to you of course if there is any thing else you need just give me a shout.
Many thanks again.

brenneke
27-03-2012, 21:00
Thanks for that both Brit and Sako. If my barrel is shagged, looks like i will be able to do an 8x57 - pretty happy about that (and yes, i appreciate it could be interpreted as sacreligous on a BSA). I will check the bolt stop first, though.

deerwarden
27-03-2012, 22:13
I have a 7x57 with the same prefix as yours, its excepionaly accurate, took many trophies with it in Africa includeing a trophy Kudu, will never sell it because of above, but bought a complete trigger assembly from John Knibs twenty years ago. Some where I have the adjustments in an american book listing many models and disassembly, they were called the Royal if my memery is correct, will try to find it as there is a precise method of setting sear and weight of pull. deerwarden.

brenneke
27-03-2012, 22:24
Try to google BSA royal rifle de Haas and you should get the de Haas google book link.

Brithunter
28-03-2012, 00:34
The De Hass book is good but expensive now... My own copy is in police custody still ......................... we think as they took it. Otherwise I would have looked it up in that.

The Hunter model became the Royal line up of:-

Regent (Short Action)
Viscount (Medium action)
Imperial (Long action)
Emperor Magnum

In 1956.

brenneke
28-03-2012, 00:37
The De Haas book is available as a google book - i was just looking at it. Go to google books and seach de haas bolt action rifles and it will take you straight to the book. The BSA pages are all there, completely free to read - i love google!

Sako3006
29-03-2012, 19:57
BRILLIANT thanks for the De Haas tip, says it all brenneke thanks and Brit once again your input is at masterclass level.
I used to have one of these years ago and moved it on like a fool but I reacon I just might hang on to this one.

brenneke
02-04-2012, 04:16
Sako, what is the overall length of your reciever?

Sako3006
02-04-2012, 19:25
Brenneke when you say overall length i will give you a couple of measurements. If you are looking on the right side of the action from where the bolt handle comes to at the rear bridge to the front of the front bribge is 15.5 cm or
5and11/16" the oal is 21.75cm 7and7/8" the bolt is 7and3/8" 18.5cm long these are measured with a tape measure so are as near as dammit. Please give me a shout if you need any more info.

brenneke
03-04-2012, 00:31
Thanks again - when i thought about your magazine length measurements i started to wonder if in fact the 7x57 was chambered in the 30-06 action length, not the 308 action length. But yep, that confirms it is a medium action, and when i finally get mine it should be the same. Gives me lots of options down the track.

Sako3006
03-04-2012, 06:39
You are very welcome and I hope the project goes well and please keep us up to date with it.