I want to add more "leade" to my 223 RPR chamber. For the purpose of being able to load my 80gr bullets out longer (more powder, less pressure, more velocity). Is this feasible with the right tool, and what tool do I need? Do I need to re-finish the area that is cut afterwards?
RPR 223 - modify chamber
- Thread starter adamg
- Start date
Curious idea. What is your load now? Are you already at max pressure? Have you tried loading with jam and seeing the results? What are your expectations? Maybe just go to another calibre like 6 or 6.5? Maybe just go to .223 AI.
No offense intended, If you were qualified to do the work, you wouldn't need to ask. If you are thinking it through for your own understanding but getting a smith to do it, that would be better.
You need a lathe and a custom reamer with a longer throat. That isnt cheap and will take time. That would let you seat you bullets longer without increasing the jam into the lands. But if you are already getting pressure signs, a longer throat wont practically let you add more powder.
No offense intended, If you were qualified to do the work, you wouldn't need to ask. If you are thinking it through for your own understanding but getting a smith to do it, that would be better.
You need a lathe and a custom reamer with a longer throat. That isnt cheap and will take time. That would let you seat you bullets longer without increasing the jam into the lands. But if you are already getting pressure signs, a longer throat wont practically let you add more powder.
cut a throat deeper takes just a few minutes with a throat reamer. no need to remove the barrel.
deeper throat is usually done on single shot rifles because there is a good chance amo dont fit in magazine.
the increased velocity may be lower than you expect
deeper throat is usually done on single shot rifles because there is a good chance amo dont fit in magazine.
the increased velocity may be lower than you expect
I'm having to load the 80gr ELDM at about 2.390" to stay off the lands. The magazine will take a length of 2.600". So I'd like to add another 0.100 - 0.120" to the freebore/throat/leade. And the bullet has a lot of bearing surface inside the case mouth at 2.390" so it will be fine up to that 2.600".
Current load development seems to be at about the limit. 80gr ELDM, 2.390", 13 degrees C. H4895 up to 22.3gr with punched primer 1 out of 4 rounds and big craters on the other primers. Varget up to 23.2gr, which is heavily compressed and again showing lots of primer cratering.
My next steps are going to involve doing next set of load development with higher case volume cases and a Chargemaster for powder measuring. I would also like to be able to go longer length as the third trick to push this system's accuracy and velocity.
dero, where can I get a throat reamer in .224"?
Current load development seems to be at about the limit. 80gr ELDM, 2.390", 13 degrees C. H4895 up to 22.3gr with punched primer 1 out of 4 rounds and big craters on the other primers. Varget up to 23.2gr, which is heavily compressed and again showing lots of primer cratering.
My next steps are going to involve doing next set of load development with higher case volume cases and a Chargemaster for powder measuring. I would also like to be able to go longer length as the third trick to push this system's accuracy and velocity.
dero, where can I get a throat reamer in .224"?
Give Manson Reamers a call, tell him what you want to do. You are looking for a throating reamer; you will likely need an extension, because the barrel will not be removed, you'll be working through the length of the receiver. No refinishing is required.
You could make a dummy round with the bullet seated to magazine length, then carefully ream the throat until the dummy will just chamber. Or, seat the bullet a bit deeper, and ream until there is slight "jam" - then you have a bit of leeway for experimentation.
You need a careful, light touch when doing this reaming. Doesn't need a whole lot of effort to do this reaming, you are only removing a slight amount of steel.
You could make a dummy round with the bullet seated to magazine length, then carefully ream the throat until the dummy will just chamber. Or, seat the bullet a bit deeper, and ream until there is slight "jam" - then you have a bit of leeway for experimentation.
You need a careful, light touch when doing this reaming. Doesn't need a whole lot of effort to do this reaming, you are only removing a slight amount of steel.
Brownell is a good place to order from. Be prepared to pay $100.00 or so after US$ conversion and shipping. If you've never done this job before, it's probably best to leave it to the professionals. What I don't get is that Ruger advertises the .223 RPR having a .556 NATO chamber which already should have the longer throat compared to the standard 223Rem chamber.
easy to do with a Uni-throater but be careful who you get to do it and how it is done. Not done properly you can end up with a throat that is not square to the bore and it will cause bad accuracy issues. They are a quick fix but to do the job correctly one should order a reamer to the specific throat length and lead angle you want an set the chamber ahead slightly. Will be a better fix to your problem
Yes, this is a fact that disappoints me about the RPR. Even my 55grn FMJ-BT loads that I make up for my AR15 at 2.245" are about as long as my RPR will accept. It has a pretty darn tight headspace, which I am OK with, but the freebore being more like a .223, in a 1/7" twist "5.56" precision rifle barrel makes no good sense.
No first hand experience, but I got my gunsmith to ream out my nitrided kel tec barrel and my walther barrel...
The kel tec was no problem, but he said he had a hell of a time cutting the walther nitride layer
Not sure where the ruger will fit in, but it could be quite a fight if its anywhere the quality of walther nitride
The kel tec was no problem, but he said he had a hell of a time cutting the walther nitride layer
Not sure where the ruger will fit in, but it could be quite a fight if its anywhere the quality of walther nitride
I get most of my stuff from BigHorn Sales
you will also need all pilot sizes to make sure you have the right one. best option might be to get it done by a smith who build match rifles
