question abour how to choose a reamer
- Thread starter dero338
- Start date
Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
As long as you have at least 2 thou clearance on each side of your loaded ammo, you will be fine.
NO, tight neck chambers do not make the chamber any more accurate. The bullet is long gone before the case neck expands anywhere near enough to hit the chamber wall.
More important is the throat dimensions and with a belted rd, the dimensions for the belt and case in front of that belt.
Jerry
paperslayer
Regular
- Location
- Chilliwack
for gosh sakes, speak with the guy who will build your gun please.
There are many things that make life easier for the plumber by letting him get involved. Garbage cheap solid pilot reamers are the last thing a plumber wants to see, and letting him measure your bullets helps too. for example, there was a real problem with Berger's 7mm bullet tolerances between die changes and it required non-standard throat dimensions for certain lots.
There are many things that make life easier for the plumber by letting him get involved. Garbage cheap solid pilot reamers are the last thing a plumber wants to see, and letting him measure your bullets helps too. for example, there was a real problem with Berger's 7mm bullet tolerances between die changes and it required non-standard throat dimensions for certain lots.
tanks Jerry this is exactly the info I was after
to answer to paperslayer, I am the one who will build my rifle
if I can make a modular stock fully adjustable for a swede mauser and make that gun put 3 shots in one inch at 300 yards, I think I can chamber a barrel
to answer to paperslayer, I am the one who will build my rifle
if I can make a modular stock fully adjustable for a swede mauser and make that gun put 3 shots in one inch at 300 yards, I think I can chamber a barrel
Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
dero338, best thing to start with is the brass you will be using. Measure up the belt. It varies quite a bit from brand to brand/lot to lot.
Also the diameter of the case right in front of that belt. This is very important and likely a couple of thou is enough. On a match style rifle, this area can be "overly" tight cause you are using your prepped cases not off the shelf ammo.
Ideally, you want the reamer to make a 90 deg cut where the belt ends. General shape is a bevel or slope so varying brass will still chamber. Great for the fire and forget shooter but allows the brass to bulge in front of the belt when repeatedly shooting the same case.
Years back, a guy built a very nice F Open rig but decided on the 6.5 Rem mag of all things. Knowing that belt area could be problematic, he went so far as to turn all his belts to the same dimension. Now his custom reamer with tight fitting belt area fit his prepped brass perfectly and he didn't have issues with case bulge.
Way more fuss then most will want to deal with but if you are building a full on rig anyways and have the gear, a few more minutes "truing" up the belts will serve you well. I guess, you could also just turn the belts OFF the case
Then send down the cases to the reamer cutter so they know exactly what you are trying to achieve.
You haven't said what type of bullet you want to use so I would suggest you just leave the throat/leade SAAMI BUT I would get a separate throater. Now you can play with extending the throats later to suit whatever whiz bang slug you want to send.
I played with a few different leade angles and saw exactly NO difference. In discussion, I usually got a nice chuckle.... no matter what angle you may have cut, in a hundred rds, it has burnt away to whatever the flame front desires.
1.5 deg seems to be the most readily available throater leade angle and that is all I use now.
Jerry
Also the diameter of the case right in front of that belt. This is very important and likely a couple of thou is enough. On a match style rifle, this area can be "overly" tight cause you are using your prepped cases not off the shelf ammo.
Ideally, you want the reamer to make a 90 deg cut where the belt ends. General shape is a bevel or slope so varying brass will still chamber. Great for the fire and forget shooter but allows the brass to bulge in front of the belt when repeatedly shooting the same case.
Years back, a guy built a very nice F Open rig but decided on the 6.5 Rem mag of all things. Knowing that belt area could be problematic, he went so far as to turn all his belts to the same dimension. Now his custom reamer with tight fitting belt area fit his prepped brass perfectly and he didn't have issues with case bulge.
Way more fuss then most will want to deal with but if you are building a full on rig anyways and have the gear, a few more minutes "truing" up the belts will serve you well. I guess, you could also just turn the belts OFF the case
Then send down the cases to the reamer cutter so they know exactly what you are trying to achieve.
You haven't said what type of bullet you want to use so I would suggest you just leave the throat/leade SAAMI BUT I would get a separate throater. Now you can play with extending the throats later to suit whatever whiz bang slug you want to send.
I played with a few different leade angles and saw exactly NO difference. In discussion, I usually got a nice chuckle.... no matter what angle you may have cut, in a hundred rds, it has burnt away to whatever the flame front desires.
1.5 deg seems to be the most readily available throater leade angle and that is all I use now.
Jerry
