Tight Chamber Advice
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Doom2
Well-Known Member
OP, you wanted a 284W but you gave the GS a piece of brass of somewhat unknown sizing. If you implied the this is what you expected to chamber he may have cut the chamber shorter than normal which would have left the base area of the chamber undersized. You should have asked him to show you that the rifle would chamber a Go Gauge.
Giving the GS a piece of brass was a mistake. Its one thing to not specify a reamer and letting the GS chose with no guidance as to bullet to be used but giving him a piece of unfired brass is just plain confusing.
Giving the GS a piece of brass was a mistake. Its one thing to not specify a reamer and letting the GS chose with no guidance as to bullet to be used but giving him a piece of unfired brass is just plain confusing.
I recently got back a 338 Lapua AI that was at the GS over a year. Chamber was supposed to be Ackley .004 crush and .260 freebore. What I got was .010 headspace and about 5/8" freebore. I wasn't going to waste time fireforming and just chuck it (carbon barrel can't setback) but decided to try it. Shot yesterday at 1015 yards - 300 gr Bergers in 11 lb all up rifle at 2975 fps. I could cover first 7 shots on target with my hand. I don't like the chamber but its a shooter. You never know.
clbrown23
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interesting perspective. this is my first gun build and now after talking with many other smiths I have learned a lot of GS ask for a dummy round like you stated Willy, seated to the desired length. this particular smith said he has built many 284 wins for the exact bullet I was referring, said he was familiar with Lapua brass I was planning to use and provided him. So Doom, a virgin piece may confuse you it must not have been confusing to the Smith because I was just following with what they instructed.
Like I stated this was my first build, I did a lot of research but having not done it before wasn't familiar with the entire process. I was trusting on the expertise, guidance and instruction from the Smith to build a tailored to the components and expectations I asked for.
I'm not willing to take the blame for "confusing" the Smith by giving him a virgin piece of brass.
Like I stated this was my first build, I did a lot of research but having not done it before wasn't familiar with the entire process. I was trusting on the expertise, guidance and instruction from the Smith to build a tailored to the components and expectations I asked for.
I'm not willing to take the blame for "confusing" the Smith by giving him a virgin piece of brass.
clbrown23
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Doom not trying to come off like a grumpy hag, but this process has been more than frustrating. Maybe I did confuse them, wish there would have been more questions asked before work was performed then so we would be on the same page.
Anyway I appreciate the applicable advice that has been provided, I will give it a try.
Thanks
Anyway I appreciate the applicable advice that has been provided, I will give it a try.
Thanks
Doom2
Well-Known Member
No problem. I understand Grumpy and Frustrated. After your explanation my post is somewhat out of line. Sorry about that.
A lot of good info from members Bob and Bill.
Size your brass and check your seating with a Hornady Oal gauge. Then load some up and shoot. You can ask your GS for a copy of the Reamer print.
When we have JGS make us Reamers for tight chambers, we make a "Dummy" cartridge and they make it to our specs. If anything doesn't work right it is on us because it is what we ordered..
One thing about a tight chamber you can Turn the Necks or open the neck up in the chamber and the FB can be lengthened. There are cutters to make these modifications. Remember a Tight chamber can be opened. A Loose chamber will always be loose.
Size your brass and check your seating with a Hornady Oal gauge. Then load some up and shoot. You can ask your GS for a copy of the Reamer print.
When we have JGS make us Reamers for tight chambers, we make a "Dummy" cartridge and they make it to our specs. If anything doesn't work right it is on us because it is what we ordered..
One thing about a tight chamber you can Turn the Necks or open the neck up in the chamber and the FB can be lengthened. There are cutters to make these modifications. Remember a Tight chamber can be opened. A Loose chamber will always be loose.
Deleted - duplicate post.
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If there are special instructions, sometimes the invoice shows it. When you gave the piece of Lapua virgin brass to the GS , what exactly did you ask him to do with it?
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Chamber reamers (well, any reamer) is what's called a form cutter. It can do nothing other than cut the hole to the dimensions of the reamer. The words "tight chamber" get thrown around a lot, and they're pretty meaningless. You can have tight headspace, but the chamber will always cut to the precise dimensions of the reamer.
You could theoretically have a situation where the smith cuts the tenon short of the specified length, which would result in a shorter chamber depth- and excessive case protrusion from the breech in order to obtain proper headspace.
If I had to guess with the limited information presented, I would focus on the necks of your Lapua brass.
The reamer cut a .323 neck (assuming it was SAAMI per the print above). It would be unlikely that your brass- with no boolit even in the neck to expand it- would exceed that diameter but if you have a mike or calipers to measure I'd start there.
FYI...
"Dummy rounds" are used when a customer wants a chamber tailored to specific brass dimensions and a specific bullet/seating depth/jump.
If a customer handed me a piece of virgin brass, when I'm supposed to cut a SAAMI chamber I'd ask why.
A dummy round can be used as the basis for a custom reamer- including specific neck dimensions/clearances (turn/no turn, type/thickness of brass), as well as freebore. The .284 Win chamber has zero freebore, but does have a longer than usual, shallow angle throat- a "typical" throat is 1.5 degrees, the .284 is about half of that. So, you end up being able to seat bullets further out than if it were a 1.5 degree throat, but not nearly as much as if you probably will need.
You said you told the smith the bullet you were going to use- what is it??
The fact that you're building on a LA, would indicate to me that you plan on using heavy bullets- if not, you could've stuck with a 2.8" OAL and a short action. So, if that's the case a SAAMI chamber and throat- makes zero sense, you'll never be able to seat that bullet out in the case to take advantage of the long action. When a custom neck isn't needed, I'll chamber with a SAAMI reamer and throat it separately to get the needed freebore for the bullet. Entirely possible the smith knows the freebore needed to run your selected bullet- but you never mentioned him stating that he would need to throat it longer?
You should question the smith as to what reamer he used, and whether he throated your chamber to facilitate your bullet selection. If not, I'd be suspect he didn't do "right" by you.
You could theoretically have a situation where the smith cuts the tenon short of the specified length, which would result in a shorter chamber depth- and excessive case protrusion from the breech in order to obtain proper headspace.
I'm curious about this. How far did the case go into the chamber? This would have had to be really obvious for you to notice it.
If I had to guess with the limited information presented, I would focus on the necks of your Lapua brass.
The reamer cut a .323 neck (assuming it was SAAMI per the print above). It would be unlikely that your brass- with no boolit even in the neck to expand it- would exceed that diameter but if you have a mike or calipers to measure I'd start there.
FYI...
"Dummy rounds" are used when a customer wants a chamber tailored to specific brass dimensions and a specific bullet/seating depth/jump.
If a customer handed me a piece of virgin brass, when I'm supposed to cut a SAAMI chamber I'd ask why.
A dummy round can be used as the basis for a custom reamer- including specific neck dimensions/clearances (turn/no turn, type/thickness of brass), as well as freebore. The .284 Win chamber has zero freebore, but does have a longer than usual, shallow angle throat- a "typical" throat is 1.5 degrees, the .284 is about half of that. So, you end up being able to seat bullets further out than if it were a 1.5 degree throat, but not nearly as much as if you probably will need.
You said you told the smith the bullet you were going to use- what is it??
The fact that you're building on a LA, would indicate to me that you plan on using heavy bullets- if not, you could've stuck with a 2.8" OAL and a short action. So, if that's the case a SAAMI chamber and throat- makes zero sense, you'll never be able to seat that bullet out in the case to take advantage of the long action. When a custom neck isn't needed, I'll chamber with a SAAMI reamer and throat it separately to get the needed freebore for the bullet. Entirely possible the smith knows the freebore needed to run your selected bullet- but you never mentioned him stating that he would need to throat it longer?
You should question the smith as to what reamer he used, and whether he throated your chamber to facilitate your bullet selection. If not, I'd be suspect he didn't do "right" by you.
Bret GRAVELINE Graveline
Well-Known Member
Bottom line is you are entitled to the firearm you commissioned him to build for you,
not a firearm he thinks you should have,
from a liability stand point the gun should and needs to function with 284 ammo,
Did the bolt start to cam and lock up at all, if not sounds like it could be a tight neck, try sizing a case with the recapping pin removed and check to see if it will chamber,
Is the barrel marked other than 284 Winchester? Such as 284 match perhaps tight neck if it is did you ask for it,
I've been retired for over 10 years but unless things changed the customer is always right,
I always listened to what the customer wanted and unless it was unsafe or terribly impractical would offer other suggestions, Otherwise you are paying me for what you want and that is what you are entitled to.
not a firearm he thinks you should have,
from a liability stand point the gun should and needs to function with 284 ammo,
Did the bolt start to cam and lock up at all, if not sounds like it could be a tight neck, try sizing a case with the recapping pin removed and check to see if it will chamber,
Is the barrel marked other than 284 Winchester? Such as 284 match perhaps tight neck if it is did you ask for it,
I've been retired for over 10 years but unless things changed the customer is always right,
I always listened to what the customer wanted and unless it was unsafe or terribly impractical would offer other suggestions, Otherwise you are paying me for what you want and that is what you are entitled to.
