Think CF2 only came in long action so only one length for spring? Viscount, medium length bolt, shorter spring?
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Think CF2 only came in long action so only one length for spring? Viscount, medium length bolt, shorter spring?
Probably true re strength but the lugs on the hunter are smaller than the CF2 and these are smaller again than my Rem 700 which appears a much stronger action with the enclosed bolt head. Comparing them I would not like to put real snorting 270 loads into the hunter, besides it would kick like a Tikka if I did.Quote:
Originally Posted by Hunter_Nick
Do you have a measurement for a Hunter Viscount mainspring length. I dont want to cut the CF2 spring and find that it was a little off what it should be and I should have cut at 37 or 38 turns.
PS the hunter and CF2 have exactly the same diametre striker rod ( the rod that the firing pin attaches to ) but the tip section of the firing pin is shorter on the CF2.
So this game is a bit like re-building a SI or SII Landrover gearbox using parts from a Rover 90
Yes correct re CF2 action. I compared 36 turns of CF2 spring to 36 turns of Hunter and the Hunter spring is 22 mm shorter. Overall the CF2 spring is probably 50 mm longer than the Hunter but I didnt measure it.Quote:
Originally Posted by tetawa
Comes a bit of a headache not Knowing the spring lengths when new. Hard to tell what has lost tension and by how much.Quote:
Originally Posted by Moa Hunter
One thing to consider, you don't want the new spring to become coil bound when the cocking piece is in full rearward position. You could measure the donor spring when coil bound on the CF2 firing pin and compare to the length of available space on the Hunter bolt. I'm sure you have thought of this....just mentioning ;)
No hadn't thought of that. I was going to compress the CF2 spring onto the Hunter striker too see how much it could take, but that is not ideal as I could end up with an over compressed spring and slogging the firing pin attachment.Quote:
Originally Posted by Mathias
Bring on the suggestions - I dont want to balls it up
One thing to note.
If two springs are of the same wire and coil diameter and the same lenght then the one with the least coils is the stiffest spring.
Something to do with the pitch of the wind, isn't it Cam?Quote:
Originally Posted by veitnamcam
Yes.Quote:
Originally Posted by Mathias
If you think of two springs one with say 5 turns and one with ten then the one with 5 must twist each coil twice as much to compress the same amount....hence it is stiffer.
Sent from my S60 using Tapatalk
Both springs appear to be the same pitch / wind. They are the same wire diameter and same centre diameter. The difference being that the Hunter spring is sad looking and shorter for the same number of turns.
I have just compared both springs following the suggestion from Mathias above. With the CF2 spring reinstalled on it's striker rod, the firing pin attached and a panel pin through both the bolt stripping hole in the shroud and cocking piece, this has the spring in the compressed cocked position. Compressed to this point 36 winds of CF2 spring would fit nicely on the Hunter striker rod without a gap or being too tight.
This must be the answer me thinks ??
Earlier this eve I cut the CF2 spring and put the Hunter back together using it. Greatly improved half open bolt position and heavier lift but not as good as a CF2. It would be better if some worthy at some time had not filed the flat on the 'closing' side of the cocking piece to change it's angle and filed a new flat on the opening side instead of the radius it is supposed to have. Result being a stiffer bolt lift and less positive half open bolt.
Looking closely at the trigger to find the problems, I think it is nearly all down to pawl engagement. The surfaces are beaten up and need truing. Even without the cocked bolt spring pressure and just using small screwdrivers to hold the pawl forward the let-off is rubbish. I will give that a go with some 'wet and dry' taped to an ice-block stick unless someone can explain to me the proper way to do it without disassembling the trigger .
What I am really struggling with is getting the bolt to release easily. Following the correct procedure, the sear does not drop with the cocked bolt withdrawn part way back and if pushed down manually is very hard to keep there ????
Update:
Trigger fixed. I removed the trigger assembly very easily with only the spring on the ejector bar to watch and not loose.
Polished the Pawl and Bar and reset the engagement angles on the worn and rounded edges so that it would break crisply. There is a little scallop in the side of the trigger unit that gives access for the points file I used wrapped with 600 then 1200 wet and dry.
The bolt release was not working, the ejector bar had a fine burr along its length from when it was stamped out. after I dressed the edge that runs against the sear the sear didn't bind anymore and will drop as it is supposed to. The bolt will now remove three times out of four attempts
So the rifle now functions fine with a passable hunting trigger - about the same as an adjusted Tikka T3 trigger.
I have washed the trigger and bolt in thinners to remove any grit, and re-lubed
Thankyou everyone for the photos and input and for just reading and checking what I have done is correct. If I didn't have problems with posting photos here I would have put some up. Will post some when shes bedded and scoped