Omark Bolt dimensions or Rem 700

[littlebang556]

Just wondering if anyone might have dimesions or even a detailed engineering drawing for Omark bolt.
I am looking to order some parts from the US but want to run the specs past supplier before I commit.

Cheers

Rob Alman

[Razer]

Hi Rob, is there any particular reason for wanting to get Omark parts made in US?
If you go to <www.tsengineering.com.au> [formerly MAB] they have an "exploded view" and parts list of the Omark M-44 shown.
Regards, Ray.

[littlebang556]

Razer,

The parts from the US will not be Omark parts but Rem parts...looking for any similarities mainly with Shroud, cocking piece, firing pin & F/P spring.

I would not be bothering with just standard Rem parts but David Tubb http://www.davidtubb.com/ does do a F/P Assembly modification (actually numerous mods) that decreases the lock time considerably and does away with the need to replace F/P spring on a regular basis by utilising Chrome Silicone.

I believe the F/P may need slight diameter reduction to pass through the bolthead retaining pin on the Omark but if it fits would be a worthwhile upgrade.

I may still be barking mad for even wishing the 2 assemblies might be interchangable in any way but they do look rather similar. I am sure someone will tell me otherwise but that may also be part of the question I am asking.

Follow this link to see what I am rambling about.

http://www.davidtubb.com/tcom_images/sp ... riker.html

& here for close-up of forward part of F/P

http://www.davidtubb.com/speedlock.html

& info on the springs here

http://www.davidtubb.com/cs_springs.html

All-in-all, quite a nice piece of engineering.

Regards

Rob Alman

[Razer]

Very interesting,I replaced a firing pin spring in an Omark a bit over 6 years ago. It was named "Wolff Blitzschnell speed-lock stricker spring"
and came from USA. Information supplied states "improved lock time,eliminates hard primer ignition problems and reduced or eliminated primer blow-back problems". Has "for use in Remington 700 Short,722 and 725 Short and 40X centrefire". Load rating at cocked position 32lbs.
Personally I thought it no different to what it replaced but I didn't shoot the rifle much after that.It is the only time I have replaced a firing pin in any of my rifles as none of the others[Angel,Barnard, Mauser,Sako] have given any problems.
The info sheet also credits the benefits to "increased power of the spring" "neatly squared and precision ground to provide flat seats" and that "load values could change with custom triggers or other modifications".
The only thing that I can conclude is that a Rem 700 spring will fit an Omark,maybe if you had access to a Rem bolt you may be able to disassemble both it and the Omark for comparison???
Good luck in your quest, Ray.

[littlebang556]

As far as the springs go for an Omark...I will change them when I no longer need a swanny spanner to cock the bolt....if I can do it by hand it is time for a new one...this happens about every 1500 to 2000 compressions.
I uncock when not in use so as to try and save it a little.
Any other thought on this please.

Regards

Rob Alman

[littlebang556]

Maybe I might be better to ask the opposing question...Best to look for dimensions of a rem 700 surely.

Regards

Rob Alman

[Woody_rod]

Rob,

The two actions, although looking similar, have a completely different bolt. The Rem having external lugs, the Omark a full diameter shaft - the same as the outer lugs diameter.

Although degraded often, the Omark actually is a step forward from the std Remington pattern in some ways: 3 lugs, floating bolt head, full diameter bolt shank. BUT retains some of the bad points: really crappy primary extraction (unless bolt timing is perfect), bad extractor design, flat bolt end/flat breech face (pain in the arse for loading 223 sized rounds)

Talk to TSE, they are the guys that now make them, and can probably make something for you if you want something different. Some improvements might be:

Coned bolt face / coned breech

Sako type extractor

Retimed extraction cam (handle section)

Longer, straight bolt handle - the original is funny, to stay nice

[littlebang556]

Woody, What you say is mostly true except I have become accustomed to slidding each round into the chamber manually...I do this rather than having a scollop machined at 6 o'clock to aid loading as I like my rounds to stay concentric...personal choice.

Otherwise, I am mainly aware of the differences you quote and never for a moment thought I could utilise the outer parts of a Rem in an Omark but rather looking at internal part like the FP assembly and/or individual components and/or any upgraded modifications some may have developed.

There are obviously some improvements that could be made to the standard Omark to further its competitiveness in a field of much more expensive actions and it is these that I seek to discover and share with others that find it difficult to move away from the Omark for one reason or another.

If someone in Oz sells an alternative FP spring in CS (chrome Silicone) that will not be minimum 1/2" smaller at the close of a season shooting then I will have 1/2 a dozen of them to share amongst others please.
TSE (ex MAB) springs are sad to say the least...combining modern technology with a 40 year old action appears to me to be a most sensible idea.

On a different note do tell me more of the proven advantages of having a conical fitting bolt.

Oh, and whats wrong with my bent thingame?
And where does one get a Sako type extractor?

Cheers

Rob Alman

[littlebang556]

Threads are different on shroud is one thing I have discovered but the FP compression tools available for Rem's will still work...Just enough of the thread engages...I will sleeve mine when I get some time.

Rob.

[Woody_rod]

Rob,

A few things:

Chrome silicon is like catch words like "turbo" and "millenium bug". The spring steel used happens to be that alloy - is otherwise a meaningless term, used by US makers to try and impress technically illiterate parts buyers.

I use a 6 inch dawn vise for firing pins.

The conical bolt head/breach is self explanatory isn't it? No reason not to modify the Omark bolt head a little to add a part cone to the breach. I know others do this to actions like Barnards. It will mean that you would need to fit a new barrel, or set yours back to gain the advantage. Loading each round is a pain in the arse.

I can give you a sako type extractor (and the other bits that make it work) if you want to try and fit one. You have a mill now right? Not sure how it would go with the current Omark designed bolt head. The original extractor is a POS.

With springs, just get the dimensions and they can be bought to suit. Buying a few is not that easy.

Ya know, you could make a new bolt in one piece if you were keen and had some spare time. Make it fit the action body on the outside, and like remington on the inside - including the shroud etc.

[littlebang556]

The one piece sounds like a job to do one day at the same time as all the other jobs that require SPARE time.

As for springs, the one available for Omark is also a POS (just fitted another) and am really looking for one that has a reasonable life span beyond 2000 operations.

I am otherwise ready for the new season to begin and looking forward to a full season using electronic targets.

Regards

Rob.