No No If these are the same ones I am thinking of they have no screw on caps because there is no room for them to have the screw cap with firing pin. They can only be used with very VERY underpowered loads or blow back will occur.
209 shotgun primers are very large and very hot.
There is another thread on the high road where these are explored. I don't recall which. There was someone who machined nipples for the ROA that worked with pistol primers and he discussed on the thread his experience in making the ROA work with modern primers. I believe these are used with black powder.
It can be done and has been done with pistol primers. As far as I know those who were fortunate enough to obtain a set before he stopped making them liked them a lot. I don't think his are for use with smokeless powder.
He wrote making nipples that safely contain the very large hot 209 shotgun primers in a Ruger Old Army was not practical. When I mentioned that the Ebay 209 shotgun primer pockets for the ROA were merely slide ins with no covers to be used with an anemic load to avoid blow back I was told good luck with that.
grter,
I'm not sure if you are correct or not.
I don't have direct knowledge about the details of these Mag - Spark 209 nipples for the ROA.
However, they may be designed with approximately the same size vent hole as regular #11 nipples.
They are designed to be used with all BP substitutes only and not smokeless.
And some people are already able to shoot Black Horn 209 powder with their ROA by using a duplex charge and percussion caps.
I'm not sure why there would be excessive blowback or that only under-powered loads could be used.
The amount of BH 209 being loaded may not produce all that much more pressure than other subs such as 777.
IMO it would really depend on the size of the flash hole inside of the Mag - Spark nipples which we can't see.
If they can't be used with a full chambers of sub. powders then there should be a disclaimer.
If there's none, then Mag-Spark could be guilty of being misleading, and liable for damages to anyone's gun that resulted or personal injuries.
They must have tested these nipples so that they wouldn't be open to lawsuits.
The Mag - Spark rifle nipple is made for magnum size rifle powder charges.
Whereas a revolver won't be loaded with that much powder.
This Ebay set up is used in Great Britain as a stop gap measure to use easily available (or should I say more easily available) 209 shotgun primers and bypass their strict gun laws which make obtaining any cartridge handguns very difficult for the average person.
I had some difficulty obtaining the instructions for using these nipples and was shocked to find out that using these nipples will require you to accept very low airgun type velocities if you want to safely use 209 shotgun primers. They do not mention that inconvenient fact in their marketing.
The Anvil 209 primer pockets for the Ruger were tested with 8 grains of Herco powder and a round ball.
There is data that suggests that less than 8 grains in a 9 mm case under a 147 grain bullet makes a +P+ load.
If one looks at the chart, the load of 5.7 grains of Herco with a 147 grain XTP produces 1120 FPS out of a 4" barrel. --->>>
http://www.natoreloading.com/herco/
That's far greater than air gun velocity.
"We have tested a Ruger Old Army revolver fitted with these primer pockets and using 8 grains of Herco propelling a 143 grain, 0.454 lead ball. Note no wads or fillers were used and no over the chamber lubricants or fats were used. Critically the rammer was the standard length provided as original equipment. The ball was not be pushed any deeper into the chamber than permitted by the standard rammer." --->>>
http://www.anvilconversions.co.uk/index_files/Page13768.htm
A Westlake .38 conversion that uses 209 primers has a recommended load of 3 - 3.5 grains of Herco to propel a 148 grain bullet, even though the gun has been proofed to be able to match .38 Special pressure.
Perhaps that conversion produces closer to air gun velocities. --->>>
http://www.westlakeengineering.com/products/
The Mag - Spark 209 nipples are pictured below.