Any reason that.....

If I read the question correctly, the 209 primer would go into the 45-70 module. Just curious, why 209 instead of the LRMP? Would the 209 primer be a press fit or loose like a 209 breech plug?

With my smoker rifles and BH209 powder, the shorter the better for ignition, why would the flame channel be too short? I ask because I don't know and not in anyway questioning your post.

Scat, what are you saying that the pressure testing exposed that makes the large rifle primer superior over 209 primers?

I wonder how in the world my 209s survive in my NULA with the super short breach plug? Over 40gr of N110 is easily pushing 33-35kpsi. The flash channel is almost half as long as a Savage plug.

The plug has about 1000 shots on it and the flash hole is still fine?

I own a van but that doesn't mean i dont take my Ducati out for a ride too. The reason is not relevant, it simply exists.

So the right answer is, if the 45/70 module was machined a little differently it could in theory support either a 209 primer or a LRMP. Since the 209 would be pressed in the module just like a shot shell it would have far more support than most breach plugs offer.

When i want a debate about which is better i will gladly ask for one.

OK.... calm down, you guys. We all have our favorite ways to do things, in the end most will work.

Now for my answer to the OP's question.

I made some modules designed for 209 primers, I did this using the standard 308 bolt face modules so that I could test them apples to apples against the LRMP's. These modules and plug had the exact same head space so I could swop them out in my gun with no modifications. The same flame path, the same .035 bushing hole and the same powder charges were used.

Kyle Pittman and myself shot 20 shots each using several different powders, (IMR4198, IMR 3031, H4350, and IMR4831, IIRC) 5 shots with each powder and a measured velocity using my Magnetospeed. This total 40 shots with using LRMP's and 40 shots using the 209 primers. 80 shots all together. These bullets were all 275 grain BE's, This test was done before Kyle started selling bullets. That was a lot of shooting and it took most all day to do this test. Every shot fired from Kyles rifle using the LRMP was faster than the same load using the 209 primer, all shots fired from my rifle (except for one) was faster using the LRMP than when using the 209 primer.

Now the speed difference was not a lot, usually less than 100 fps, but the big problem and the reason I did not make more of these modules and offer them to the public for sale is because the 209 primers leaked gas, not between the copper jacket and the brass module, but it leaked between the primer and copper jacket itself. They leaked bad enough that after 40 shots I could see some erosion on my bolt face. So the idea of 209 primers in a module at 50,000 psi was scrapped and I decided to just stick with what I know works and that was the LRMP.

Some of you might wonder why I didn't post this a long time ago when Kyle and I did the test, Well, this test was done when I was still on the other board and I just didn't want to start the debate. I new if I posted the results it would start another war, so I just let it go.

I abandoned all future testing with 209 primers and concentrated on building my LRMP guns.

Hope this helps...

Agree, that is the best 209 design available from what I have seen. Seeing the primer inserted into the plug shows me that it does not fit on the outer shell O.D. (carrrier) of the 209 as a crush fit. That said I would expect to see that primer leak around the primer and the carrier if you ran hotter loads. Also if there is no crush fit on the primer I would expect other leakage.

That said it is refreshing to see another system with nearly no flame path on the primer. Due to this reduced flame path I have personally seen the use of the bushings not necessary in the testing I have done on my own system thus far. To put it another way... when there is not a chamber behind the vent hole and there is minimal back flow there is also minimal errosion.

I have a curious question on the Nula plug. What are you seeing for carbon build up? The reason I ask is I have 2 theories on the carbon build up in the plug.
Theory 1 is the 209s cause it?
Theory 2 is the flame path size causes it? In this scenario the longer the path the higher the carbon build up.

Originally I suspected theory 1 but I am very strongly leaning to theory 2 now days. It would be very interesting to hear what you are seeing on carbon.

The crush on a NULA is on the rim of the primer. The recess in the bolt even supports the rim of the primer just like a shotshell. It has one drawback. Head space must be perfect and mine can only use a CCI primer. My bolt wont close with other primers. The NULA bolt does have a locking lug opposite the bolt handle so it does "cam" forward kinda like a Rem 40X rimfire action.

I can shoot it for extended periods and hardly any carbon builds up in the flash channel. Pretty much all NULA owners will tell you the same thing. My theory is with the smaller flame channel volume and near perfect seal there is very little gas moving back into the channel on ignition.

IMO a larger flash channel can erode a flash hole faster do to the larger volume. It is certainly a double edge sword and the balancing act needs to be damn near perfect for it to work. I doubt i would try it with some of the very heavy loads being used.

Another thing ive noticed with the NULA is far better fps vs the Savage plug. 58gr of N120 yields over 2400fps in my 26" barrel with a 275gr BE. Almost 2450fps actually. In a Savage you would need about 63-64gr to get the same muzzle velocity. It will even ignite 4227 far more reliably than a Savage OEM plug.

I know Hank is busy but im surprised nobody has tried making a HIS type plug for the OEM RUML barrel. Not for smokeless but for BH209. It would remedy the gas cutting issues that have popped up occasionally if the brass is reused too many times.

Im still slightly baffled as to why the NULA breach plug stays so clean and my primers have never bulged or show any sign of over pressure. Even my Knight/Lehigh plugs with a good crush on the primer gets enough carbon it needs to be cleaned more often. Its still very good though. Using Blackhorn ive easily gone 40 shots in one range session without cleaning it out.

I just dont shoot far enough to have a need for top end loads. I do find the data very interesting and think its great some like to shoot them. The last 2 years i loaded up with a cheap 350gr and 465gr lead conical moving only around 1200-1300fps. They both kill just fine.