Grouse Posted March 4, 2009 Report Share Posted March 4, 2009 For those that do bother with with prepping Lapua brass prior to loading, whats your experience on deburring flashholes? From the information on 6MMBR website it questions that the K and M tool is too big a diameter, also it makes suggestions that the decapping pin on most dies are too big a diameter is this the case with wilson neck dies? Extract from 6mmbr website- What Size are Lapua 6BR Flash-Holes and Should I Ream Them Larger? When Lapua started making 6mm BR Norma brass ten years ago, Lapua adopted a 1.50mm (0.059") flash hole size. However, Lapua tells us that production tolerances run up to 1.60mm (.063"). OK, should you ream your flash-holes to fit a standard 1/16" (.0625") decapping rod? We suggest NOT reaming. First you have to buy special tools, and you may end up with flash-holes that are bigger than you want. If you use the K&M PPC flash hole deburrer to ream the hole (from the inside) it will end up about 0.068". If you use the Sinclair 07-3000 tool (which reams from the outside), shown below, the flash-hole will end up about 0.063". The later is probably OK, but when you start to approach 0.070" we think you may be losing some of the claimed accuracy advantage of the small PPC-style flash-hole. If you want to leave your 6BR flash-holes at minimum diameter, turn down your 1/16" decapping pins or decap with a Redding or Harrell's die. The 6BR and 6PPC Redding and Harrell's dies normally ship with a .057" diameter decapping pin. (If yours is larger, ask Redding for the smaller version.) The .057" decapper will work with UN-REAMED 6BR brass. So, to make a long story short, flash holes anywhere from .059"-.063" are "normal" and a Redding die should work. But if you want to use a 1/16" (.0625") decapping pin (found on most "universal" decapping dies) you should ream with the Sinclair 07-3000 tool. UPDATE: Recent lots of Lapua 6mmBR brass have shown a little sliver of brass that can occlude the flash-hole. You will want to remove this excess brass so that the flash-hole is clear. You can do this with an inexpensive "pin-vise" and #53 (.0595") drill bit. Have got a KandM ppc tool on its way, so what do you fellas do?? Also whats the "common" neck bushing for lapua brass and 75 gr vmax and 87gr vmax? Cheers Link to comment Share on other sites More sharing options...
Ratwhiskers Posted March 4, 2009 Report Share Posted March 4, 2009 Forster 2 die set on "no neck turn chamber" it comes with the correct sized decap pin so no need to worry... Then just stick the Ratwife behind the thing , and as you've seen ..... .1 of inch" groups.... Nuf said.... Link to comment Share on other sites More sharing options...
Alycidon Posted March 4, 2009 Report Share Posted March 4, 2009 Hi, As far as I am aware K&M gear is fine, I use it to prep my brass. Use one tool to trim any exess brass from the inside of the flash hole, this goes in from the neck end, just a couple of twists will do the job, then a flash hole tool to true the primer pockets from the outside, better attached to a slow battery drill but it only wants a couple of seconds per case. The outside diameter of both those bullets should be .2430, your loaded neck size should be between 1 and 2 thou (.001 - .002) under your chamber neck size and the bushing size will be most commonly be 2 thou under that. I E, On my .270 neck I use a .266 bush, my loaded neck diameter is .2684 therefore I have 1.8 thou of grip. To work out your bush you will need to know the chamber neck size and the case neck thickness. My necks are .0127 having had a light turn. So we have .2430 (bullet OD) + .0127 (case neck)+.0127 (case neck)= .2684. Therefore the .266 bush gives me enough grip to remove a loaded round if I loaded it into the lands. Some say that 1 thou is enough. Hope this helps. A Link to comment Share on other sites More sharing options...
Grouse Posted March 5, 2009 Author Report Share Posted March 5, 2009 I have always just measured a loaded round at the neck, then deducted 2 thou from this to get bushing size - never thought it necessary to know the chamber size. Tried the decapper pin on my wilson dies and it does work fine. Was a bit concerned about deburring Lapua brass when there are a few articles saying not tot. Surprised not many more of the 6br users haven't added to this - maybe not many find it necessary to tinker with Lapua brass. Link to comment Share on other sites More sharing options...
Alycidon Posted March 5, 2009 Report Share Posted March 5, 2009 Its probably a bit anal but you know that you have made the best case you possable can. A Link to comment Share on other sites More sharing options...
Elwood Posted March 5, 2009 Report Share Posted March 5, 2009 When I get my 6 BR back ( it's a long story ) I will add to this thread, as far as I'm aware for the brief time I had the rifle in my hands I didn't do any case prep at all. 5 shots 100 yards load development. Link to comment Share on other sites More sharing options...
Grouse Posted March 5, 2009 Author Report Share Posted March 5, 2009 Agree, anal maybe, but a once in the life of the case operation - how difficult can it be?? Oh well will ask some bench shooters. Thanks for your input Aly Link to comment Share on other sites More sharing options...
Grouse Posted March 5, 2009 Author Report Share Posted March 5, 2009 Nice 5 shot groups Ellwood - Waiting for rifle to get finished and have a few weeks for prepping them before the spring influx of sh*te decends onto my area.... Link to comment Share on other sites More sharing options...
TC Posted March 5, 2009 Report Share Posted March 5, 2009 I'm in the same situation - 2 boxes of lapua brass crying out for attention and rifle held at the pleasure of the Constbulary.... The rifle will have a no turn neck (same reamer and Nightwalker I suspect) but is it worthwhile doing a 75% clean up neck turn as part of the one time prep? I have seen comment that the Lapua brass isn't as good as it was - I spotted a couple with primer hole flash in the few I looked at which I have never seen on my other Lapua brass. TC Link to comment Share on other sites More sharing options...
Alycidon Posted March 5, 2009 Report Share Posted March 5, 2009 Prepping the brass is like reloading, a labour of love, you do come to love it. Gives you something to do on winter nights!. A Link to comment Share on other sites More sharing options...
Guest varmartin Posted March 5, 2009 Report Share Posted March 5, 2009 Nightwalker....Give us a chance...had to get the hoovering done first ...LOL This is what i do... My Chamber is a .269 NK...so i turned my brass to give me a loaded round dia of .266 ( a bit sloppy, but it is a field gun ) I uniformed all primer pockets for depth. Then used a K&M de-bur tool to give a nice little chamfer on the inside of the primer hole, but left the hole size untouched. ( Try this....blow in a case like a whistle that has bee inside reamed and compare the tone to one that has not !!! ) I checked the cases for consistent length and trimmed all of them just to square up the case mouth, NOTE...1-2 thou was removed to make all even. I was going to batch weigh them but found little difference ( 1/10 of a grain ES )...WOW...so all 100 good to go. I have checked on a number of occasions but they are all still the exact same length after 10+ firings. Thats all. Link to comment Share on other sites More sharing options...
Guest varmartin Posted March 5, 2009 Report Share Posted March 5, 2009 I'm in the same situation - 2 boxes of lapua brass crying out for attention and rifle held at the pleasure of the Constbulary.... The rifle will have a no turn neck (same reamer and Nightwalker I suspect) but is it worthwhile doing a 75% clean up neck as part of the one time prep? I have seen comment that the Lapua brass isn't as good as it was - I spotted a couple with primer hole flash in the few I looked at which I have never seen on my other Lapua brass. TC I purchaced 200 cases 3 years ago ( still have a box of 100 untouched ) Link to comment Share on other sites More sharing options...
TC Posted March 5, 2009 Report Share Posted March 5, 2009 I purchaced 200 cases 3 years ago ( still have a box of 100 untouched ) Did you do any prep Martin or just run them as they are ? TC Link to comment Share on other sites More sharing options...
TC Posted March 5, 2009 Report Share Posted March 5, 2009 Did you do any prep Martin or just run them as they are ? TC Sorry Martin - just noticed the post above! TC Link to comment Share on other sites More sharing options...
Grouse Posted March 5, 2009 Author Report Share Posted March 5, 2009 Hope you did a good job on the hoovering Martin - right in the corners and everything?? LOL On a serious note I actually enjoy preping cases for an accurate rifle, but was a little concerned about articles on 6mmbr saying not to deburr cases? Also I too have seen burrs/lips on new Lapua brass TC - never saw that on the 500 cases on my 243 brass - maybe we should have just gone with the factory ammo TC like the builder says??? Link to comment Share on other sites More sharing options...
Ratwhiskers Posted March 5, 2009 Report Share Posted March 5, 2009 N/W uk. Sorry if my post seemed a bit odd/off........ it's the Med's l'm on (whoopeeeee ) When the rifle Rat Rifle was shot in the only prep was to tip the box of brass on to the bench and load it..... Yup that's it..... Nawt/zippo/zilch/nada..... and it shot into the .2's right off Fire formed brass first time through the die and inside neck trimmed shot .1's The Lad's are right.... it's a 6mmbr.... Nuf said mate!! Just shoot it, and enjoy the feeling of total confidence that you've got one of the best chamberings going. Regards. Ratty. .... Link to comment Share on other sites More sharing options...
shrek Posted March 5, 2009 Report Share Posted March 5, 2009 i second rat whiskers nightwalker, we can all get abit anal about seating depth, bullet selection, powder choice blah blah blah. Anyone who reloads knows what im talkin about, i use to case prep my 6BR, now i dont bother, load them as they come out the box and enjoy being out in the field with it knowing that i can take a shot at range and be confident in doing so. Either is a 87gr v-max for charlie or crows, 87 HP for deer or 105 A-maxs too hit silly little targets at 1000 yards None of which now get case prep, its a calibre that just seems to shoot, i could imagin that you could probably load the bullets backwards in a 6BR and you still wouldnt get over an inch at 100 Link to comment Share on other sites More sharing options...
Ratwhiskers Posted March 5, 2009 Report Share Posted March 5, 2009 Shrek. You... Knowing wot you're talking about....... That's bloody Rich Link to comment Share on other sites More sharing options...
onehole Posted March 6, 2009 Report Share Posted March 6, 2009 I will just add this because it is based on recent experience.I choose to have tight necks and neck turn because I actually quite enjoy the whole technical bit of my shooting and as -,s will know perhaps a bit too anal sometimes!? However in the past I have noticed things about cases and have had to bin perhaps one or two for various reasons but the last batch of 6br I turned down for a 269 neck showed up 3 cases that were well out of concentricity and would no way turn on the setting I was using on my neck turner without real force being applied.I gave up on them and chucked em in the bin.No great loss out of 100 but those duffers would probably have caused a flyer to ruin a group or shot. Most of the turning I do for tight necks ends up with either nil runout or at worst 3 tenths. Having said all that the bunch of 308,s around here including my trg are doing stupid groups that a 6ppc would not be ashamed of.Runout on my trg lap cases is at least a thou so go figure I thing the saying goes.cheers Onehole. Link to comment Share on other sites More sharing options...
(200x135).jpg.0fd0a94f065c6cb243fdff1b40e0819a.jpg)
.jpg.0972b4e2bdf0b5a4109eb96f2b1b62ad.jpg)
Recommended Posts
Archived
This topic is now archived and is closed to further replies.