KareImp

As long as the bullet doesn't fall out, your deep enough.

I've gone to a heavier bullet at times when I couldn't get as close to the lands as I wanted. Only when I wasn't getting the accuracy I wanted though. I don't care if the bullet is a quarter inch from the lands if it groups well (which it wouldn't!)

stubblejumper

I have fired rifles that did group well with the bullet seated .200" to .250" from the lands.

bigcountry

My 300RUM right now is seated .2" away from the rifling. I have also found some bullets like the Grand slam can be made to shoot well with it .25" away from rifleing instead of up close.

vangunsmith

That mlight be good if a person only used one type bullet all the time.the reason at times was not to have the throat cut on the reamer was that some people hogged off to much at one time when chambering and broke the reamers pilot off. Thats why they came out with other than solid pilots. One has another problem cutting the throats ,and have them centered after already cutting the chambers. vangunsmith

Roskoe

Van - your post doesn't make any sense to me. Maybe that's my fault . . . . but I have chambered quite a few rifles over the past 30 years. I currently own 67 chamber reamers - all have been used a least a couple of times - some have chambered over 100 rifles. The pilot, whether floating or solid, guides the reamer into the bore of the barrel. The floating pilot reamer holder gives the reamer the ability to track right down the center of the bore. And the barrel shank is centered, trued, and spinning perfectly on center when all this occurs. The chamber reamer is going right down the center of the bore, whether it is cutting a throat or not. And if you cut the throat a second step, the piloted throating reamer is going right down the center as well. This would be hard to screw up, unless you have been drinking! With all due respect, what am I missing here . . . .

robert49

That's interesting. I have a new 6.5x284 rifle for benchrest. The figures are for lapua brass and scenar 139 bullets:

Bullet Length 1.370"

Bullet diameter 0.264"

The minimum Cartridge Overall Length from Lapua reloading tables is 3.11"


So, by using the general rule 1.370 - .264 = 1.106" of bullet should be sticking out of the case and 0.264 should be seated in it.

Mine, however, has about 0.50" (nearly twice as much as the "rule of thumb") in the case when touching the lands and about 0.87" sticking out of the case. It is also very close to the minimum COL.

It hasn't been fired yet. Do you reckon I should get a little more freebore reamed out before I do fire a round, say around another 0.2" so I can seat the bullet a bit further out?

Thanks

Robert

rost495

IF freebore is cut correctly(regardless of others opinions IMHO) the bullet can still have a large jump and be extremely accurate(for reference purposes here I'm talking MOA or just under as extremely good hunting rifle accuracy). Its just that the free bore should be close to bullet diameter.

In your instance of having or wanting to seat way out, you can try varying the neck tension to see if that may help your grouping. Redding makes good dies for this or Jim Carstensen can adapt the size die you have. In this instance neck tension will be about the only way to help hold onto that bullet really well if its needed.

Going the other way in seating, its best not to seat below the neck/shoulder juncture BUT only because there can be a donut that will destroy accuracy hiding down in there. If thats reamed out then it will have little affect on accuracy.

I'm curious as to the rifle article, but I don't have access to the article unless someone can help me. And I despise someone posting you are all wrong due to this one article..... Let us know what it says and back it up a bit. Just because I read it doesn't mean I believe it.

Prime example is folks listening to bullet makers that claim that lead tips melt off bullets in flight. I've got enough proof that they do not melt, while others claim they do. Their only claim is from what they are told. There is too much evidence to the contrary to believe that. Not to mention required energy calculations(that are beyond my capabilities but have been presented)

Final thoughts on seating depths. There is no guarantee. ONe thing to be aware of is that seating just to touch will create varying speeds and pressures due to the fact that you each bullet can be a bit different and instead of just touching, some will be jumping, some engaged to the rifling. Some just touching. So the best rule I can give you use a minimum of 10th off or 10th engaged and go from there. Don't be in between. I've won lots of matches with engaged rounds. But then again I've won a lot of individual matches with bullets that jump a LOT. In hunting rifles I feel one should be a minimum of 15-20th off for safeties sake.

Jeff

robert49

IF freebore is cut correctly(regardless of others opinions IMHO) the bullet can still have a large jump and be extremely accurate(for reference purposes here I'm talking MOA or just under as extremely good hunting rifle accuracy). Its just that the free bore should be close to bullet diameter.

Yes, Iagree. I think mine has been cut about 200 thou too short though. Look how deeply the bullets are seated. Over twice the length of the neck.

In your instance of having or wanting to seat way out, you can try varying the neck tension to see if that may help your grouping. Redding makes good dies for this or Jim Carstensen can adapt the size die you have. In this instance neck tension will be about the only way to help hold onto that bullet really well if its needed.

No I can't set the bullet further out. It hits the lands even when deeply seated in the case. That's my problem! That's the point I'm making.

Going the other way in seating, its best not to seat below the neck/shoulder juncture BUT only because there can be a donut that will destroy accuracy hiding down in there. If thats reamed out then it will have little affect on accuracy.

Well, I am a long way further in than the neck/shoulder juction. About 0.25" in fact. I cannot do anything about that because the bullet is touching the lands already. Assuming no donut, how far into the case can the bullet go. The scenar 139 grain is a long bullet. Over half of it is in the case even when the other end is touching the lands.

I'm curious as to the rifle article, but I don't have access to the article unless someone can help me. And I despise someone posting you are all wrong due to this one article..... Let us know what it says and back it up a bit. Just because I read it doesn't mean I believe it.

I have no idea where it is. Sorry


Final thoughts on seating depths. There is no guarantee. ONe thing to be aware of is that seating just to touch will create varying speeds and pressures due to the fact that you each bullet can be a bit different and instead of just touching, some will be jumping, some engaged to the rifling. Some just touching. So the best rule I can give you use a minimum of 10th off or 10th engaged and go from there. Don't be in between. I've won lots of matches with engaged rounds. But then again I've won a lot of individual matches with bullets that jump a LOT. In hunting rifles I feel one should be a minimum of 15-20th off for safeties sake. [/quote]

Yes, but my problem is that I think my bullets are seated far too far into the case. I cannot move them out because they are touching the lands. i.e. the throat is VERY short.

There is nothing I can do about it, other than ream some more space. I think?

rost495

Robert

I'm sorry. I forget this thing replies to the last person that posted. None was directed at you. Just general thoughts.

FWIW in your case are you sure you are touching rifling or are you touching the throat? I had a very similar issue in where I thought I had the chamber designed a certain way. It was. Found out the bullets I was using were .0003 larger than others I was using and I was reading off the sides of the throat. Its why I never got a pretty rifling mark either. I just shot that rilfing the way it was supposed to be.

If I were you, I'd find out what the exact chamber dimensions were and at what length you should be able to seat the lapua bullets.

If in the end the throat needs to be longer it can be cut.

Jeff

bigcountry

No, I don't. Your in a good situation. Yes, its further in the case than your use to, but different bullets will seat different ways.

How does matchkings do? Or typical hunting bullets?