CVA Paramount

[Huntingjeff]

I was just thinking since the bolt face was spring loaded head spaced if you could find the proper oring or a soft thin walled copper or high temp plastic washer it may work.

 

[ronlaughlin]

......could it be possible to use o rings to help seal?

Well i sure don't know how o-ring would work in the paramount, but i do know they work good in Accura, Optima, and Omega.

Here is a comparison of 209 primer, adapters, and an RCBS #12 shell holder.

 

[Dougs136Schwartz]

I think Ron did something like that with his Omega? plug using the LRVF modules from Cecil. Orings though dont work well with the twisting of the bolt. Since the Paramont bolt does not hold the primer i guess its a possibility but not likely.

That is a good point . I have never used o rings but i could see how that would be a problem with most bolt actions .

One thing is for sure . CVA has definitley stirred some interests

 

[Huntingjeff]

My thought was since the paramount bolt head does not hold the primer or adapter and you are inserting it by hand and my undstanding that the bolt face is stationary as it closes and is compressed by the spring it might work

 

[Huntingjeff]

And as I said I was thinking about the original variflame adapters that were the same as a 209 I no the large rifle are bigger after thinking about it.

 

[Busta]

Well i sure don't know how o-ring would work in the paramount, but i do know they work good in Accura, Optima, and Omega.

Here is a comparison of 209 primer, adapters, and an RCBS #12 shell holder.

The length in the Vari-Flame II is essentially the same length as a 209, but what are they exactly? 0.300"?

All it would take to use a 209 primer, is a breech plug with the correct diameter primer pocket. Most are in the 0.243" to 0.245"ish ballpark, but CVA uses a metric 6.4mm (0.252") diameter 209 primer pocket in their QRBP that are better fits for the slightly larger diameter 6.22mm (0.245") European 209 primers. I use the NSI Nobel Sport primers in mine. They are also as long as the old Winchester W209, at 0.300"+.

Would be real easy to shoot 209 primers with just s breech plug change. Also if the bolt head is self headspacing with a spring, just a matter of replacing the spring with a proper shim for a 0.003"ish crush fit.

I've gotten o-rings to work in modified Knight DISC Breech Plugs, but everything has to be perfect. Otherwise the camming action of the bolt van turn the o-ring right out with the 209 primer. But it can be done with a little patience.

 

[Huntingjeff]

Bustsa that’s what I was saying from what I’ve heard true or not??? The bolt face does not cam it stays stationary as the spring loads. There shouldn’t be a need for shims as the spring creates surface pressure on the bolt nose to ( keep it sealed) I’m just thinking just in case. As you can tell I have no intrest in the paramount lol, I’m trying to fix it before it’s broke.

 

[Huntingjeff]

Oh I see what your saying with the 209s and crush fit, I was still thinking the variflame. But your European primers may help there also. Where are you purchasing them, if you don’t mind?

 

[GM54-120]

In theory a 209 plug upgrade looks pretty simple and it can even be made like my NULA plug with 100% of the primer in the plug. Only the rim of the 209 would not be in the plug. The HUGE advantage of this is the primer is totally supported and can tolerate high pressures without bulging. Im absolutely sure this is true because ive shot numerous loads in my NULA that are easily over 32kpsi. Some are probably over 35Kpsi. Another advantage is it seals on the primer rim crushed between bolt and plug.

The only negative is its very primer specific. The primer pocket needs to be cut to fit your 209 and head space is critical but not impossible either.

When my NULA bolt is cammed shut there is no gap at all. There is no way the primer can bulge. The Paramount since it has no extractor looks like an ideal candidate for this style.

 

[Chick]

View attachment 3792

Yeah, I remember he 25 ACP version.

 

[Chick]

Well i sure don't know how o-ring would work in the paramount, but i do know they work good in Accura, Optima, and Omega.

Here is a comparison of 209 primer, adapters, and an RCBS #12 shell holder.

So, do they, or you, supply the bushing to fit LR primers and fit in the 209 BP?

 

[ronlaughlin]

Prbullet supplies/sells them. However, they won't fit in a 209 BP. See comparison photo in post #62 above, see they are larger than a 209 primer. What i did was use a 9/32" end mill, to enlarge the diameter of the 209 breech plug to accept the VariFlame adapters, and while at it, made the socket deeper to allow the use of the o-ring.

 

[Dougs136Schwartz]

ahhhh Thats what you did . Did the Variflame adapters leak without the Oring ?

 

[ronlaughlin]

Yes they leak. They are very durable. Made of stainless. Good for many many shots. Not at all able to conform to the breech plug like a 209 primer can when tight. For me, the o-ring is necessary.

 

[GM54-120]

I wonder if sealing could be improved just by adding a "snout" like the ASG modules. Maybe even small enough OD to fit a 5/32 flash channel.

Lukes 223 based module might fit a modded Omega plug. If im reading the specs correctly its about .378 on the rim but Lukes modules are smaller than the rim.

 

[ronlaughlin]

Looks like the body of the modules is about 5/16". If so, it seems like the Omega plug could be easily modified to use the modules. Probably not a compelling reason to do so, for just shooting Blackhorn. Is there a standard shell holder that fits the module?

 

[GM54-120]

223 shell plate for the one i mentioned. They are designed to fit in a 223 bolt head for CF to ML conversions. Most people use the .473 plates (308Win) for bolt action conversions but Luke offers these too.

IMO the benefit is you can use a large variety of LR and maybe LP primers. LR Mags for BH209 and milder ones for Triple7 although im unsure if they would be mild enough to reduce the crud ring. The major benefit is they do seal very well. Its a extremely well tested design.

Over $5 a module though and sold in packs of 20. So its a rather costly experiment.
http://www.arrowheadsporting.com/arrowheadplug_lrmp.html

 

[ronlaughlin]

What is most interesting, to me anyway, is i am most comfortable using a completely stock factory Omega breech plug. When Blackhorn first became available about 10 year ago, i first shot it in the Omega. Never had an issue, never knew there was an ignition issue using the powder. Alas, i had to try new things, plus i read of other's problems, and got involved. Well i guess that is what is called 'full circle'. Started shooting Blackhorn with a bone stock Omega; today i shoot Blackhorn with stock Omega(s) using the same primer, same sabot used the very first time.

No good reason, for me, to look at the modules, or anything else; cost is not an issue.

 

[Dougs136Schwartz]

When dealing with Blackhorn I just can not see any advantage to a LRP system over 209s. I have tried. You will gain a little speed depending on plug design. The good LRP systems use brass modules . I had problems with my modules corroding with Blackhorn. They were a real pain to clean. Myself I would rather have a good sealing 209 system that i can just chuck the spent 209s when im done. If I thought there was a accuracy advantage I would have all my rifles converted regardless of brand.

 

[Dougs136Schwartz]

Sorry to get off topic just more or less agreeing with Ron