1967spud Posted January 24, 2011 Report Share Posted January 24, 2011 Ive just tried my hand at meplat trimming for the first time, i am trimming some berger 7mm 180 g vlds. Now the query i have is that the bullets are running from 1.507 to 1.515 in total length so there is an extreme spread of nearly 10 thou . I was wondering do i take and average across 20 rounds and trim for a set overall bullet lenth distance to where the meplat is ok for them all or do i trim each individual meplat back by the same distance irrespective off overall bullet length. I will then go on to weight sort them and further sort by bearing surface(i think) Any help would be appreciated. Link to comment Share on other sites More sharing options...
andybrock Posted January 24, 2011 Report Share Posted January 24, 2011 Ive just tried my hand at meplat trimming for the first time, i am trimming some berger 7mm 180 g vlds. Now the query i have is that the bullets are running from 1.507 to 1.515 in total length so there is an extreme spread of nearly 10 thou . I was wondering do i take and average across 20 rounds and trim for a set overall bullet lenth distance to where the meplat is ok for them all or do i trim each individual meplat back by the same distance irrespective off overall bullet length. I will then go on to weight sort them and further sort by bearing surface(i think) Any help would be appreciated. Sorry Spud I havn't got an answer to your question but rather another question for you, what do you hope to gain with meplat trimming, is it just for consistency or is there some other reason? never done it myself just like to know. Cheers Andy Link to comment Share on other sites More sharing options...
Foxshooter Posted January 25, 2011 Report Share Posted January 25, 2011 I shall be expecting big things from you at the range this weekend mate if you are putting all this effort into your reloading. You will be running out of excuses! Mark Link to comment Share on other sites More sharing options...
6.5shooter Posted January 25, 2011 Report Share Posted January 25, 2011 While talking about the meplat subject, id be interested to hear about the trimming but also, is meplat pointing a success and is it much of a benifit? I understand it will increase bc but is it really worth it for the little gain? Garry Link to comment Share on other sites More sharing options...
1967spud Posted January 25, 2011 Author Report Share Posted January 25, 2011 Sorry Spud I havn't got an answer to your question but rather another question for you, what do you hope to gain with meplat trimming, is it just for consistency or is there some other reason? never done it myself just like to know. Cheers Andy more uniform meplats leading to slight increase in bc figures resulting in slightly less verticals for distance shooting Link to comment Share on other sites More sharing options...
andybrock Posted January 25, 2011 Report Share Posted January 25, 2011 more uniform meplats leading to slight increase in bc figures resulting in slightly less verticals for distance shooting Thanks for the explanation. Link to comment Share on other sites More sharing options...
terryh Posted January 25, 2011 Report Share Posted January 25, 2011 Spud, Re. trimming, you cannot really use LOA for guaging the meplat trim as your bullets might be different in the first place. The tool normally references to the Ogive so this is the 'bit' you're uniforming to, the diameter of the meplat, if just trimming, is the area of interest. Same meplat diameter = same drag = same negative acceleration. What sort of trimmer are you using? If it is a 'plastic' bodied one e.g. Sinclair, then you will have some difference as the amount of effort you push the bullet into the trimmer with will change the reference distance. i binned my sinclair for one of these: http://www.bullettipping.com/meplattrimmer_detail.asp metal body, no deveation. also this tool body can be mounted into a caliper for measuring bearing surface length etc. nice touch. Re. bullet pointing, the first tool out was the Widdens (see here: http://www.whiddengunworks.net/pointingdie.html ) which was pretty good. The second gensration tools (see; Here http://www.bullettipping.com/bullettippingdie_detail.asp ) have a better fit and fell to them. I've found using a Lee hand press (http://www.leeprecision.com/cgi/catalog/browse.cgi?1295943451.2698=/html/catalog/rlpress1.html#Reloader ) you can feel the pointing going on, you can also sit in front of the TV etc. and point a whole slew of bullets in comfort The question 'is it worth it. Well the claims are for between 4 and 8% improment in BC, obviously the trim and point on smaller calibres will have the greater effect - the meplat is porortionally bigger to the bullet diameter. But if you took a conservative 5% improvment in say a 139g 6.5mm Scanar you take it from the claimed G1 of .578 to over .6 - this is 'free', no extra powder, no extra barrel wear etc. Here's some DTAC's I just pointed in the past using the Widdens tool (no trimming) FYI: What you need to consider personally is 'is it worth it to me'? Brgds Terry Link to comment Share on other sites More sharing options...
6.5shooter Posted January 25, 2011 Report Share Posted January 25, 2011 Youve got me thinking now Terry. Might give it a try for my 6.5. Do you see a noticiable change in elevation at long range? Wind might be harder to see the change but was wondering if the difference in performance majes it worth it. To me if i can gain a little it is worth it. Read about this a while back but never got speaking to anyone who has actually tried it. Garry Link to comment Share on other sites More sharing options...
terryh Posted January 25, 2011 Report Share Posted January 25, 2011 Gary, I did some 'down and dirty' testing at 600 yards using DTACs in my 6x47, ignoring wind and just concentrating on holding the elevation I found apprx 3" less drop at this distance, using the same load, brass, primers etc loaded at the same time, just pointed and non pointed bullets being the only difference. Verticle spread also appeared less between the two groups, they were shot alternate to allow for any fouling issues. If you worked it back this was just over 5% improvment in BC. As I said, it's for free and one of the simpler things to do, if you're really being picky you can use a Junke (sp?) machine to cull any off centre lead cores/thin jackets, measure the bearing length of each bullet, sort by weight, meplat trim and point, just down to time and money (as always) If you want to send me some bullets I'll trim and point them for you to try (not too many please ) Brgds Terry Link to comment Share on other sites More sharing options...
6.5shooter Posted January 25, 2011 Report Share Posted January 25, 2011 Terry, I have 700 123 scenars sitting on the shelf, ill send u 350 this week to keep u going and 350 next week :lol: How bout that? Im only jokin, i think i will send away for the kit to have a go at it, il take youre word that its a success. Do you trim the meplats before pointing aswell? Did you have any problems getting the set posted over here? Also, can you purchase 115 DTACS over here or do you have to order them from the states? Was just wondering, have been thinking lately of doing a 6-6.5x47 and because we only shoot 600 yard fclass in the North of Ireland here i think it would be a good choice for it. Garry Link to comment Share on other sites More sharing options...
terryh Posted January 25, 2011 Report Share Posted January 25, 2011 Gary, I trim the meplat then point you end up with a very consistent 'nose' on the bullet. , The guys will send stuff but I normally put together an 'order' and have a friend mail it to me, I'm about to do this so shout if you want some help! I normally bring in bullets en-mass but I believe Norman Clark keeps DTAC's. The 6x47 is an excellent med-range F-class (it will go to 1000 yards but you'll loose out to the bigger cartridges in any wind ) A good friend who's a serious F-Class swears by this round. PM inbound Brgds Terry Link to comment Share on other sites More sharing options...
6mmBR Posted January 25, 2011 Report Share Posted January 25, 2011 I use a 6x47 for short range F class and it is a very capable round. Mine unfortunately doesn't like the DTAC's very much and shoots 105 Berger VLD's a lot better. My standard load is 40gns N160 with a 105 10 thou into the lands this gives a MV out of my 30" barrel of 3070 fps. Been experimenting with reloader 17 and with 40 gns I'm getting 3250 fps with the same bullet, with no pressure issues. The load however is a smidge less accurate but I think I will put up with this to get the advantage of an extra 200fps. Now got to try and test bullet pointing on the Bergers and see if that crisps up the slight vertical with bthe load. As far a DTAC's are concerned I know HPS stock them, but I bought mine straight from Dave Tubb in the States as they have the necessary paper work and export licenses. Cheers Dave Link to comment Share on other sites More sharing options...
terryh Posted January 25, 2011 Report Share Posted January 25, 2011 Dave, Out of interest what twist in your 6x47? I went with 7.5 as others had found the 8's sometimes did not work the DTAC's. Also found N550 worked well in this case. ATB Terry Link to comment Share on other sites More sharing options...
6mmBR Posted January 25, 2011 Report Share Posted January 25, 2011 Hi Terry, your right mines a 1 in 8 good with Bergers but not wonderful with DTAC's. It does group but I'm getting 3/4 - 1 MOA at 300 yards but with the 105's I'm getting 1/4-1/2. Hopefully the good velocities with the Bergers will offset the slightly lower BC. I did try N550 but found N160 gave me far more uniform velocities. Cheers Dave Link to comment Share on other sites More sharing options...
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