Lyman Great Plains question

[Prairiewolf]

I read somewhere that it's a good idea to use a .38 cal bore brush to clean the bottom of the bore, something about a cavity where the powder sits or something? Is that true? And what is the shape of the very bottom of the bore? Is it flat, or concave? It would help me to clean it if I know how it's configured or shaped.

 

[Grenadier1758]

It is true that your GPR has a reduced diameter breech area. While a brush can be used to clean the breech, a little bit of care can keep the fouling from blocking the breech.

If you wipe between shots, use a damp patch and don't run the patch all the way to the patent breech. Occasionally with the damp patch at the breech, fire a cap to clear fouling from the flash chamber. That damp patch will pull all sorts of fouling flakes.

You have a hooked breech. It is simple to pull the wedges to remove the barrel during cleaning. Remove the nipple and with the breech in a bucket of warm water, the flushing action of the cleaning will clean all the fouling from the breech. I like to use WD40 to displace water as I dry the bore. Before putting the gun away, I use a good rust inhibiting lube and I store the rifle with the muzzle down allowing the oils to drain away from the breech. Before your trip to the range, wipe the bore with an alcohol dampened patch to remove the remaining oil.

 

[Maven]

This -> You have a hooked breech. It is simple to pull the wedges to remove the barrel during cleaning. Remove the nipple and with the breech in a bucket of warm water, the flushing action of the cleaning will clean all the fouling from the breech. I like to use WD40 to displace water as I dry the bore. Before putting the gun away, I use a good rust inhibiting lube and I store the rifle with the muzzle down allowing the oils to drain away from the breech. Before your trip to the range, wipe the bore with an alcohol dampened patch to remove the remaining oil. ...curator

 

[SDSmlf]

I am a proponent of using WD40. With rules. After cleaning flood barrel with WD40 (assuming hooked breech here), follow up with a complete wiping with a dry patch(s). Now an important step. Store barrel/gun muzzle down for a minimum of 24 hours to allow WD40 to drain. If going to the range, good to go after firing a couple of caps to clear breech of any residual oil. If hunting, I flood with isopropyl alcohol and allow to dry before loading. I use the 91% alcohol. I pump with dry patch night before gun/loading. You want the chamber area cleared of any oil.

Figure out a method that works for you and then stick with it.

 

[fishmusic]

I have a .50 cal GPR and I use a .38 cal mop to clean the fowling from the patent breach. A second mop with a patch will dry it. WD40 , swab dry and then Barricade rust preventor.

 

[Prairiewolf]

I found this drawing of a "patented breech". Is this basically what the Lyman GPR breech looks like? This is really what my question was about.
http://mamaflinter.tripod.com/id13.html

 

[Zonie]

Technically, the drawing in your link shows a "chambered breech".

That is what many of the modern guns made at the big factories and sold by Lyman use.

The true Nock's Patent breech looks like this



Note the small chamber that runs crossways to the barrel.
This small chamber was intended to fill with powder during loading. When the powder ignites the small chamber creates a jet of flame that passes thru the hole at the bottom of the bore to instantly ignite the main powder charge.

Nock was a noted gunmaker and one of his competitors, unable to use his patented idea designed the chambered breech to obtain a similar improved ignition system.

Then, there is the Ardesa Patent (often called a CVA patent). Their design with the drum creating a sort of a patent breech while also locking the breech plug into the barrel is common on the Spanish made rifles.

This in included in the drawing of various breech designs I made which shows below.

 

[fishmusic]

Zonie,

Thanks for the education. :hatsoff:

 

[fishmusic]

Prairiewolf,

Zonie gives a good explanation on the distinctions between traditional and modern breaches. I always learn something new from his posts.

I swab between shots with Doug Schoultz's moose milk but have not yet had fouling in the breach that causes a misfire. I keep my gun very clean and always clean the fire channel when I clean the barrel.

Not being a hunter I cannot recommend what to do in the field.

 

[AZbpBurner]

While a .38 cal brush works fine to clean out the patent breech to remove whatever hot soapy water leaves behind, some cautions: use a nylon brush only - they seem to be built better than the bronze brushes. Bronze brushes are difficult to remove when they come apart. Always crosspin your rod tip before using it in any rifle, since the rod tip with attached brush or patch jag is also difficult to remove when stuck in the bore.

 

[charlie b]

I have a GPH and do what is stated above.

I add one more. I use a brush (mine is brass) I think it is .32 cal brush. When I first got the gun I put it in the barrel and used a drill to spin the rod/brush and then inserted it in the breech chamber.

After that I wrap a cleaning patch around the brush and use that to clean and swap the breech area every time I clean the gun. I use WD40 to get the water out after cleaning.

When getting ready to go to the range I use rubbing alcohol on the patch around the brush to get all the WD40 out of the chamber.

If I wipe the bore between shots it is after loading the powder and seating a veggie wad (I shoot mostly bullets). If I am shooting PRB I do not wipe between shots.

 

[Smokey Plainsman]

After flushing with water and swabbing the bore, I use a .30 bore brush with a patch twisted over the tip of the brush to clean the chambered breech on my GPR. Works nicely.