What do all of you think about muzzle breaks for 30 BR ? I read a few threads about them. I'm starting to have problems with my neck (bad disks) since I started getting more recoil from shooting with the rear bag 2" from the butt of the stock. I probably won't shoot in any competitions other than local range shoots. I read that Harrell brakes work just as well as the Vias, and are only about $35.00. I read that some people have them reamed out to .020 over the bullet diameter so they don't effect the accuracy. Does anyone know a very good gunsmith in northern Illinois area to install a brake ?
How much Runout is acceptable ?
- Thread starter short range
- Start date
If you don't plan to shoot comp. , 4 groups are ok. Generally the nearest flags have more effect than those farther out, but each range has their own specific quirks such as terrain, roof downdrafts, etc.. Can't help with brakes, I know they help with hunting rifles. They are not allowed in registered short range comps. I also have neck and back problems, but recoil does not seem to aggravate them. Carrying the gator bag and rest is worse than shooting.
I don't shoot bench rest anymore (not since the 222 in the 70's) but I like all my match bullets well under 1 thou (like to see no more than a flicker on the dial. anything around 1+ will go into my "sighters" -we are only allowed 3. But to be fair I take my loading way beyond most and it is probably not all necessary. I am a machinist and do everything I can to dies, brass, bullets etc. I anneal every second shooting, neck turn, weight sort, trim, etc etc etc call it an obsession as I believe wholeheartedly in "sum of all the little things matter". I am regularly beaten by guys that don't do anything like this but are good at reading wind and mirage. At 1000 yards 1 mph wind shift can mean 6-8 inches. Mirage nearly as devastating and makes all this seem insignificant to most.short range said:
But IMHO I believe runout in some rifles can make a significant difference (even 2 thou)
Thanks guys, It sounds like most of the registered competitions are at least 5 or 6 hours from me, so I doubt if I will go to any this year. Do you guys know if any competitions that are close to northern Illinios ? Al told me when i bought the rifle, that he had to travel quite a ways and he lives in southern Wisconsin.
For registered shoots go to International Benchrest Shooters site....click on "ranges" and "schedule- score matches".
I believe the 2" reference is the bag to end of stock distance. But Alf may have a point, you also may have your shoulder back too far. I don't have recoil issues with the 30 BR ( other than bag upset), and like you, I have neck problems also. Large caliber hunting rifles, on the other hand, do aggravate those discs.
I believe the 2" reference is the bag to end of stock distance. But Alf may have a point, you also may have your shoulder back too far. I don't have recoil issues with the 30 BR ( other than bag upset), and like you, I have neck problems also. Large caliber hunting rifles, on the other hand, do aggravate those discs.
thanks guys, I'll try the light shoulder pressure. Alf, do you know of any registered shoots that are in our area ?
Sorry about pulling the subject back to the OPs original topic, but way back on page 2 or 3 when we were talking about run-out and the Hornady tool vs the V-Block type, that I have. I said I had a new Hornady unit on order, and when it arrived I would do a little comparing and post the results.
First, I must say the Hornady unit is well made, with good close tolerances in the machine work, and the dial indicator is of better quality than I expected, even if it is made in China.
The two types of run-out tools, like Hornady's Lathe type and the V-Block type operate differently. As the Lathe type holds only loaded rounds at both ends, and you take the reading from just in front of the case neck, on the bullets baring surface (Mfg Recommended test location) With the V-Block type you can take reading any place on the case or bullet you want, even test empty brass, therefore the V-Block type has some advantages by design.
I ran some simple non scientific comparison tests, all reading's are taken just in front of the case neck to keep things as fair as possible. I used two different calibers, round A and B are both 6MM BRs with 80g Berger's from the same reloaded lot. And round C is a 308 with a 168g SMK.
All three rounds have been reloaded several times using Forester bushing type neck sizing dies, Redding seating dies, and all work was done on a Forester Co-Ax press.
V-Block Hornady
A .004 .0015
B .002 .0005
C .003 .002
C* .0035 .0005 (* Note: This 308 reading was taken 1/4" below the meplet)
Round test C* was taken to show what happens with the Hornady unit when you try to take a reading closer to the bullets meplet, on a Lathe type tester. The closer you get to either end of the round, the lower the numbers will be, and its the opposite on a V-Block unit.
Also, on round A I tried to use the run-out straightener, by pushing the bullet up to .016 (4X its run-out) in the direction of its low side, but it failed to reduce the run-out. So in my opinion, on this round, the correction part of the Hornady unit doesn't work.
Even though the Hornady unit reads about half or less of what a good V-Block unit will, it still gives you a run-out reading, and the run-out direction, so it can still be used, though I would recommend using the hand method with an empty case to straighten any run-out, as I do with my V-Block unit.
The Hornady's other draw back is, it will only test loaded rounds, not empty brass, so it ranks lower for versatility.
I will keep this new Hornady unit anyway, as its of the Lathe type, and is well made, and may have some other uses with some modifications.
Mike.
First, I must say the Hornady unit is well made, with good close tolerances in the machine work, and the dial indicator is of better quality than I expected, even if it is made in China.
The two types of run-out tools, like Hornady's Lathe type and the V-Block type operate differently. As the Lathe type holds only loaded rounds at both ends, and you take the reading from just in front of the case neck, on the bullets baring surface (Mfg Recommended test location) With the V-Block type you can take reading any place on the case or bullet you want, even test empty brass, therefore the V-Block type has some advantages by design.
I ran some simple non scientific comparison tests, all reading's are taken just in front of the case neck to keep things as fair as possible. I used two different calibers, round A and B are both 6MM BRs with 80g Berger's from the same reloaded lot. And round C is a 308 with a 168g SMK.
All three rounds have been reloaded several times using Forester bushing type neck sizing dies, Redding seating dies, and all work was done on a Forester Co-Ax press.
V-Block Hornady
A .004 .0015
B .002 .0005
C .003 .002
C* .0035 .0005 (* Note: This 308 reading was taken 1/4" below the meplet)
Round test C* was taken to show what happens with the Hornady unit when you try to take a reading closer to the bullets meplet, on a Lathe type tester. The closer you get to either end of the round, the lower the numbers will be, and its the opposite on a V-Block unit.
Also, on round A I tried to use the run-out straightener, by pushing the bullet up to .016 (4X its run-out) in the direction of its low side, but it failed to reduce the run-out. So in my opinion, on this round, the correction part of the Hornady unit doesn't work.
Even though the Hornady unit reads about half or less of what a good V-Block unit will, it still gives you a run-out reading, and the run-out direction, so it can still be used, though I would recommend using the hand method with an empty case to straighten any run-out, as I do with my V-Block unit.
The Hornady's other draw back is, it will only test loaded rounds, not empty brass, so it ranks lower for versatility.
I will keep this new Hornady unit anyway, as its of the Lathe type, and is well made, and may have some other uses with some modifications.
Mike.
Thanks Mike - Good review.
If you get the time could you try measuring a few cases at the neck/shoulder junction in lathe and then behind meplat (where hornady contacts bullet) in V Block. This is where approx. max runout should be for both and it would be interesting to see if the figures are comparable
Thanks
Cam
If you get the time could you try measuring a few cases at the neck/shoulder junction in lathe and then behind meplat (where hornady contacts bullet) in V Block. This is where approx. max runout should be for both and it would be interesting to see if the figures are comparable
Thanks
Cam
Attachments
Cam, Will do, but I'm not quite sure just where you want the readings taken. Would you like several rounds tested on the case neck and as close to the neck/shoulder junction as I can get them, and again just below the meplet, and with both tools for a comparison?
The Hornady tool comes with three different bullet end holders, the only difference is in the size of the bullet tip hole. The middle size hole was installed from the factory, but to get closer to the meplet I installed the smallest hole unit. To change this only takes 5 sec. But I thought the smallest hole would work best. You can also set the amount of spring pressure on the bullet, but you cant allow the bullet to rotate the tip holder and ball handle. If it doesn't rotate, you get zero side movement in the tip holder, so I set mine so it had only a light spring pressure, plus the round will rotate easier that way.
On the Hornady unit, accuracy is also somewhat reliant on the case head being round and aligned with the case body, so on my test rounds, I checked the case heads for roundness, and alignment, (on the V-Block unit) and all of the Lapua case heads tested were within .001 of being round and true.
In looking at your exaggerated picture, the Hornady unit would read the highest if taken at the neck to shoulder junction, as the round rotates on a center line axes between the center of the case head and the meplet. But with a V-Block unit the highest reading would be close to the meplet, as every thing above the body to shoulder junction is cantilevered out, and unsupported.
Mike.
The Hornady tool comes with three different bullet end holders, the only difference is in the size of the bullet tip hole. The middle size hole was installed from the factory, but to get closer to the meplet I installed the smallest hole unit. To change this only takes 5 sec. But I thought the smallest hole would work best. You can also set the amount of spring pressure on the bullet, but you cant allow the bullet to rotate the tip holder and ball handle. If it doesn't rotate, you get zero side movement in the tip holder, so I set mine so it had only a light spring pressure, plus the round will rotate easier that way.
On the Hornady unit, accuracy is also somewhat reliant on the case head being round and aligned with the case body, so on my test rounds, I checked the case heads for roundness, and alignment, (on the V-Block unit) and all of the Lapua case heads tested were within .001 of being round and true.
In looking at your exaggerated picture, the Hornady unit would read the highest if taken at the neck to shoulder junction, as the round rotates on a center line axes between the center of the case head and the meplet. But with a V-Block unit the highest reading would be close to the meplet, as every thing above the body to shoulder junction is cantilevered out, and unsupported.
Mike.
BoydAllen
Gold $$ Contributor
The H & H solves the problem of alignment between case head and body , is well built, can be used to straighten, and covers a wide selection of calibers. I have one and it works well.It is easy enough to use that I was able to straighten all of my rounds to a maximum of about .00075 as part of my loading routine between matches at an NBRSA sanctioned 1-200 yd. match. http://benchrest.com/hnh/concentricity2_files/page0001.htm
Mike - Thanks that would be great and yes they are the points. I drew both pictures (1 rotated through bullet point and case head like hornady and one around case body like V Block) in one of the other threads and will try and get them back up again. Indeed the points taken should be neck shoulder junction (or just on neck or just body behind shoulder) in Hornady as this is the point of max runout. On the V Block as close to Meplat as possible. I think the V Block should give a slightly higher reading but they should be the same order of magnitude.
Boyd. The H & H looks like a nice piece of equipment.
Boyd. The H & H looks like a nice piece of equipment.
I found the picture again. The diagram on left is exagerated runout and rotated around centre axis of shell like a V Block does. The diagram on right is same but rotated around a line between bullet tip and base (like hornady).
1) First thing you will notice is max runout is at bullet tip on V blocks but at neck shoulder junction on hornady or "lathe type". So to get the best (or highest in each case) reading on your runout it should be at point f on the V block and point c (or b) on the lathe type.
2) Next you will notice the "magnitude" of measured runout is less on the lathe type even though runout is the same. (distance from f to centreline on left is greater than c to centreline on right).
One of the issues with the lathe type is you cannot measure the "roundness" (as opposed to concentricity) of the bearing points. On a V block you can simply move the dial over the top of the V block as you pointed out Mike.
Now we have some new cross breed V/lathe combinations such as the H&H. Indeed they have moved the contact point further down the body of the shell and therefore would get away from the case head vs body runout issue but again the "roundness" should be checked at the V block. Also by moving the contact point further down the shell, the runout measurement is reduced again. Not that I see this as a big issue as it is still measurable it just must be taken into consideration when comparisons are made
1) First thing you will notice is max runout is at bullet tip on V blocks but at neck shoulder junction on hornady or "lathe type". So to get the best (or highest in each case) reading on your runout it should be at point f on the V block and point c (or b) on the lathe type.
2) Next you will notice the "magnitude" of measured runout is less on the lathe type even though runout is the same. (distance from f to centreline on left is greater than c to centreline on right).
One of the issues with the lathe type is you cannot measure the "roundness" (as opposed to concentricity) of the bearing points. On a V block you can simply move the dial over the top of the V block as you pointed out Mike.
Now we have some new cross breed V/lathe combinations such as the H&H. Indeed they have moved the contact point further down the body of the shell and therefore would get away from the case head vs body runout issue but again the "roundness" should be checked at the V block. Also by moving the contact point further down the shell, the runout measurement is reduced again. Not that I see this as a big issue as it is still measurable it just must be taken into consideration when comparisons are made
Cam, to try to answer your questions, I tested 4 rounds, at two locations, and on both types of tools. From your post, I'm sure you understand the different reading produced by the different types of tools, and why, but maybe others will be helped by the test results. And hay, this threads not long enough anyway.
I tested 4 rounds of 3 different calibers.
A = 223 w/69g SMK
B = 6BR w/105g VLD Berger
C = " " " " "
D = 308 w/168g SMK
With round standing with the bullet up.
Reading taken just above the case neck
V-Block Lathe
A = .005 .002
B = .001 .002*
C = .004 .0015
D = .0045 .001
Readings taken just below the meplet
A = .006 .000
B = .001 .0005
C = .001 .0005
D = .0045 .0005
* I'm not sure why this round tested as it did, and I tested it twice. And round C's two V-Block tests are interesting, any ideas?
Mike.
I tested 4 rounds of 3 different calibers.
A = 223 w/69g SMK
B = 6BR w/105g VLD Berger
C = " " " " "
D = 308 w/168g SMK
With round standing with the bullet up.
Reading taken just above the case neck
V-Block Lathe
A = .005 .002
B = .001 .002*
C = .004 .0015
D = .0045 .001
Readings taken just below the meplet
A = .006 .000
B = .001 .0005
C = .001 .0005
D = .0045 .0005
* I'm not sure why this round tested as it did, and I tested it twice. And round C's two V-Block tests are interesting, any ideas?
Mike.
Thanks for those readings Mike they are interesting to say the least and good examples of different types of runout.
Round C. -I saw this when I used to try and hand straighten. The neck is bent out and when you straighten the bullet tip back in (on V block) the tip bends back in line with body but neck stays and still sticks out the side. It can also happen if you have a really good seating die (fits well at body and bullet seating stem is in line with body, but has a bit of neck clearance like my home made seating collet for redding) and it tries to load straight (at tip) but the neck is out of line.
Round A is classic and as expected.
B? not sure - will do a few sketches and have a think - must have a few bends out and back as well. If you still had it separate it would be worth checking in a few extra spots with V block. 1) roundness of case at V block locations. 2) shell just in from neck mouth and 3) shoulder of bullet at start of ogive.
I would guess by looking at these that you have a good 6BR seater that fits your shells well but the neck sizing or FL die you are using is giving a little runout. Your 223 and 308 results are pretty normal and simple to understand with one bend at the neck somewhere
As far as the tools go at these points the lathe is obviously hardly showing any runout when there is indeed some there. Perhaps further down the neck towards shoulder might improve a bit but still not as clear as the V block.
Cheers, and thanks again.
Round C. -I saw this when I used to try and hand straighten. The neck is bent out and when you straighten the bullet tip back in (on V block) the tip bends back in line with body but neck stays and still sticks out the side. It can also happen if you have a really good seating die (fits well at body and bullet seating stem is in line with body, but has a bit of neck clearance like my home made seating collet for redding) and it tries to load straight (at tip) but the neck is out of line.
Round A is classic and as expected.
B? not sure - will do a few sketches and have a think - must have a few bends out and back as well. If you still had it separate it would be worth checking in a few extra spots with V block. 1) roundness of case at V block locations. 2) shell just in from neck mouth and 3) shoulder of bullet at start of ogive.
I would guess by looking at these that you have a good 6BR seater that fits your shells well but the neck sizing or FL die you are using is giving a little runout. Your 223 and 308 results are pretty normal and simple to understand with one bend at the neck somewhere
As far as the tools go at these points the lathe is obviously hardly showing any runout when there is indeed some there. Perhaps further down the neck towards shoulder might improve a bit but still not as clear as the V block.
Cheers, and thanks again.
Cam, I agree with your analysis of the numbers, they do tell allot. I do have these 4 round marked and just dropped back in there boxes, so retesting them or at least round B is no trouble, and now I'm curious about its readings.
One thing that comes to mind, is the fact that both Dial Indicators have ball tips on them, but, my Starrett is about 1/16" in diameter and the one on the Hornady is smaller, (Ill also get these ball measurements in .000" rather than guess) so scratches, or any imperfection in the bullets can make the needle jump at times, but you do soon learn to disregard them.
Ill run some more tests tomorrow on round B just for fun, and maybe we can figure it out.
One other thing, if I'm going to take case neck readings, remember non of my case necks have been turned.
Mike.
One thing that comes to mind, is the fact that both Dial Indicators have ball tips on them, but, my Starrett is about 1/16" in diameter and the one on the Hornady is smaller, (Ill also get these ball measurements in .000" rather than guess) so scratches, or any imperfection in the bullets can make the needle jump at times, but you do soon learn to disregard them.
Ill run some more tests tomorrow on round B just for fun, and maybe we can figure it out.
One other thing, if I'm going to take case neck readings, remember non of my case necks have been turned.
Mike.
Thanks Mike and understood - In this case I would recommend trying a reading on body just under shoulder for the lathe (point b on picture above for those looking on)- might be a higher reading than the bullet depending on bullet length vs body length. For the V block you are probably in the best spot to give you best indication.
What neck sizer are you using for your 6BR. I might be able to post you a couple of parts to try??
I appreciate the input and am sure a few other readers will get something out of it so am happy to return any favours I can.
Cheers,
Cam
What neck sizer are you using for your 6BR. I might be able to post you a couple of parts to try??
I appreciate the input and am sure a few other readers will get something out of it so am happy to return any favours I can.
Cheers,
Cam
Retest of Round "B"
V-Block Hornady
At meplet .0006 .000
Just above case neck .0011 .002
center of case neck .003 .0023
body at shoulder junc. .0005 .0011
Ball diameters, Starrett .120 Hornady .108 (but Hornady must be a little larger, (.120?) as its a trapped ball bearing). So there about the same, per the stick of truth.
The Hornady may be best if your looking for a banana case, as the case shoulder is close to my front V-Block with BR cases, so it will read low runout at that point.
Mike.
V-Block Hornady
At meplet .0006 .000
Just above case neck .0011 .002
center of case neck .003 .0023
body at shoulder junc. .0005 .0011
Ball diameters, Starrett .120 Hornady .108 (but Hornady must be a little larger, (.120?) as its a trapped ball bearing). So there about the same, per the stick of truth.
The Hornady may be best if your looking for a banana case, as the case shoulder is close to my front V-Block with BR cases, so it will read low runout at that point.
Mike.
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