SMI Breech Plug & Vent Liner

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308xp

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Oct 24, 2019
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It appears that the SMI website is gone and I need a spare Breech Plug and some Vent Liners for an NEF 50Cal conversion. This conversion was just made in the last few months.

And, if anyone has a copy of the SMI load data that they had on their web site I would really like to have copy of that also.

After getting the conversion done and then, by the time I got the time to start shooting it...SMI seems to have disappeared from the web.

Any help would be appreciated.
 

GM54-120

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Cant help on the plug but not long ago someone posted a pic of the actual SMI load data they sent out with the conversions/rifles. I will post it when i can find it.
 

ported45

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It appears that the SMI website is gone and I need a spare Breech Plug and some Vent Liners for an NEF 50Cal conversion. This conversion was just made in the last few months.

And, if anyone has a copy of the SMI load data that they had on their web site I would really like to have copy of that also.

After getting the conversion done and then, by the time I got the time to start shooting it...SMI seems to have disappeared from the web.

Any help would be appreciated.

You may have to send your plug off to a gunsmith to have one (or two) custom machined for you.
 

308xp

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Cant help on the plug but not long ago someone posted a pic of the actual SMI load data they sent out with the conversions/rifles. I will post it when i can find it.
Thanks...That's exactly what I am looking for.

As to a custom Breech Plug...I'm afraid you might be correct.
 

308xp

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Oct 24, 2019
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Anyone have any guess as to the life span of an SMI Breech Plug? Certainly it depends on the loads, But using moderate loads...
1000 rounds???? More ??? Less??

Could it be I don't NEED a Spare?
 

dozer_xj

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I have an SMI Encore. I also noticed the website was down when looking for loads. I bought it used. It came with two breech plugs. One had a vent liner in it. I am thinking about drilling and tapping my second one out to accept a vent liner. I was doing some research and I read that Lukes plug from arrowhead sporting goods is the same thread and sealing surface but it is longer. I contacted Luke and he said he did not have time but recommended I contact Hollis at Center Punch USA.
 

GM54-120

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The guy who posted on Dougs linked his pics so i wont bother doing it again here.

I will say this though. SMI used 4198 a lot but in the Savage it is really really slow for even a 300gr bullet. N120 is a far better powder for this application and lots of guys here used it in their SMIs. Ive shot it in my NULA 50 with a 1-32 Douglas barrel. It really gets a 275gr BE moving good with just 57-58grs. Reloder7 is another good one and i think SMI had data for Re7 too. A little dirty but a good powder because its double based and temp stable.
 

308xp

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Yeah, I got those pictures of the Load Data posted on Doug's...So I don't need it again. Thanks.

My question still stands...How long would a Breech Plug last with Moderate loads? I know that's a very subjective question but a good guess would be helpful. Of course, I'm talking Breech Plug here NOT vent liners.

I'm thinking that if the Breech Plug is a very long lasting part, then Maybe I'll have the Vent Liner hole in my current BP tapered to accept the Savage vent liners and then use them or the Lehigh version. Does that sound reasonable?
 

GM54-120

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Cant say but my NULA plug has many many shots (well over 500) on it and its still fine. A lot has to do with the volume of the flash channel and how well the primer seals.

Better the seal and smaller than volume....The longer a flash hole stays in spec. Then then type of steel used and amount/type of powder used play a part too. Larger amounts of slower powder open up a flash hole faster.
 

Sideshow

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Oct 14, 2019
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I have an SMI Encore. I also noticed the website was down when looking for loads. I bought it used. It came with two breech plugs. One had a vent liner in it. I am thinking about drilling and tapping my second one out to accept a vent liner. I was doing some research and I read that Lukes plug from arrowhead sporting goods is the same thread and sealing surface but it is longer. I contacted Luke and he said he did not have time but recommended I contact Hollis at Center Punch USA.
Thanks i needed that information on who to contact for a custom breechplug !!!! Im suprised nobody responded on DWB considering parts are hard to find and with a little thought big upgrades are possible . Just sayin . Thanks again.
 

Duhawki

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Dec 23, 2007
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I have a 50 cal SMI barrel on a H&R Ultrarifle frame. It was built for me about a decade and a half ago. I noticed the SMI website is gone and the old phone number in Upland is disconnected too. I'm guessing out of business? I also have concerns about my breech plug and erosion of the 0.030 hole. The thread size is 9/16 - 18. I do see the Arrowhead guys list one of that thread. could it be threaded to use a Savage vent liner? Are there any other options I should consider? Thanks!
 

GM54-120

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You could tap the plug for 10-32 threads and use a Lehigh vent liner. You would also need a 82 degree counter sink bit if my info is correct.

Required a 5/32 drill bit, 82 degree spotting drill, 10/32 tap, and a vent liner
 

Duhawki

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Dec 23, 2007
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I appreciate the info. Does anyone know what really happened to SMI? Or how to contact the dude that ran it?
Regards,
Duhawki
 

308xp

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Oct 24, 2019
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Rumor I heard was that he passed away.
If someone knows his name (Ron..something...I think). They could google an Obituary. Then let us know.
 

308xp

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Oct 24, 2019
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I'll Bet this was him:
Ronnald "Ron" Eugene Name, 75, Hartford City, Indiana, passed away at 8:07 p.m. Wednesday, Aug. 14, 2019, at IU Health Ball Memorial Hospital. He was born in Kokomo on Sept. 28, 1943, to Everett Lewis Name and Rosaline (Kessler) Name. Both of his parents preceded him in death.
Ron graduated from Kokomo High School in 1961. He served in the United States Air Force from Aug. 9, 1961, to May 21, 1965. He married Paula Irene (Hollingsworth) Name on Jan. 11, 1964, in Galveston, Indiana.
He was a member of Full Gospel Lighthouse Tabernacle Church, Telephone Pioneers of America, Amateur Trap Shooters Association and NRA. He enjoyed fishing, hunting and deer hunting.
 

SMI

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We are still In business making muzzleloader barrels.
I am Dan DeWitt I have been Ron's partner in the business since we started making barrels in 1984.
if you have any Questions please call me at Shop PH. NO. 765-998-7320
 
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