njc110381 Posted July 13, 2010 Report Share Posted July 13, 2010 Right chaps. I've always thought myself to be a fairly competant reloader but I've come across something that's really got me beat! So I'm looking for some pointers! My combi gun isn't grouping too well. Never really has and this has been confirmed by the fitting of the scope. I can't get inside 4" at 100 yards with the factory ammo I have and I think I've just sussed out why! I've always loaded about 20 thou from the lands, maybe more with Barnes TSX. Well as an experiment I thought I'd draw a pencil line around the bullet against the case and give it a few taps with the kinetic hammer to pull them out a bit, then stick them in the rifle and close it to get the approximate max OAL for that bullet type by seating them with the throat of the rifling. All seems simple you may say? What's the problem? Well... Factory ammo is 2.855 OAL. I've hammered them out to 3.122 and pencilled a second ring on the bullet. They still close with no resistance. I tapped it a little more and out it fell, so less than a bullet width was inside the case at last known measurement! ****! What should I do next? Quote Link to comment Share on other sites More sharing options...
al4x Posted July 13, 2010 Report Share Posted July 13, 2010 sell it and buy a proper gun or take the logical step and load 3 at 10 thou, 3 at 15 thou etc and shoot paper and see what works. Quote Link to comment Share on other sites More sharing options...
markbivvy Posted July 13, 2010 Report Share Posted July 13, 2010 What should I do next? start at 30 thou of then 40 then 50, find out where it want them. keeping a look out for signs of pressure. Quote Link to comment Share on other sites More sharing options...
njc110381 Posted July 13, 2010 Author Report Share Posted July 13, 2010 (edited) That would be the logical step. The major problem is that I don't know where max OAL is to back off from? The bullet has fallen out of the case before it gets close to the lands! EDIT... I should clarify that I've never reloaded for this rifle yet. The measurement from max OAL is what I do with my other guns. Edited July 13, 2010 by njc110381 Quote Link to comment Share on other sites More sharing options...
Harnser Posted July 13, 2010 Report Share Posted July 13, 2010 You have got to know your maximum O.A.L before you can start to back off . Try the old trick of loading a bullet in an unprimed case so that it just sits in the case . use black felt tip ink on the bullet and then lock the dummy round down into the breech the bullet will then be pushed into the case and you will see the marks on the bullet where the the lands have touched the ogive . You are now at maximum O.A.L. Harnser . Quote Link to comment Share on other sites More sharing options...
njc110381 Posted July 13, 2010 Author Report Share Posted July 13, 2010 You have got to know your maximum O.A.L before you can start to back off . Try the old trick of loading a bullet in an unprimed case so that it just sits in the case . use black felt tip ink on the bullet and then lock the dummy round down into the breech the bullet will then be pushed into the case and you will see the marks on the bullet where the the lands have touched the ogive . You are now at maximum O.A.L. Harnser . I know. I did that with the bullet just about held in the case by about 1mm and it came out just the same with no sign of being pushed in (like you'd expect it to be). Quote Link to comment Share on other sites More sharing options...
al4x Posted July 13, 2010 Report Share Posted July 13, 2010 can you get a longer bullet? just for getting the initial measurement otherwise all I can suggest is going in increments of 5 or 10 thou over the length of the factory ammo and trying to see if that makes a difference to accuracy, if not refer to my initial post Quote Link to comment Share on other sites More sharing options...
njc110381 Posted July 13, 2010 Author Report Share Posted July 13, 2010 I nearly replied to your initial post but the site censor would have blanked it all out so there was no point! I do need to find some longer bullets. I was thinking 175grn RN (I'm using 140RN now). Quote Link to comment Share on other sites More sharing options...
al4x Posted July 13, 2010 Report Share Posted July 13, 2010 I can only guess if you have a wide range of weights available and some are very heavy then the gun must be made to account for this and you have got rounds on the light / short side hence you can't find the lands. Quote Link to comment Share on other sites More sharing options...
AndyCM Posted July 13, 2010 Report Share Posted July 13, 2010 I nearly replied to your initial post but the site censor would have blanked it all out so there was no point! I do need to find some longer bullets. I was thinking 175grn RN (I'm using 140RN now). Hi, Are you intent on RN bullets - they are stumpy for weight, but with (relatively) plenty of bearing surface compared to a regular "pointy" bullet, and so your gun may just not like them. I'd be inclined to go with a regular bullet - Hornady Accubond, Nosler BT type stuff and match weight to twist - forget thou and go SAMMI, tweaking with powder only initially and only playing around SAMMI a little if needed. Cheers AndyCM Quote Link to comment Share on other sites More sharing options...
seeker Posted July 13, 2010 Report Share Posted July 13, 2010 Have you tried a rod from the front to touch a bullet that has been dropped into the throat: mark rod when it touches the front of bullet then a second mark where the rod touches the breech face? .. a bit fiddly but could be easier with a combo barrel? Quote Link to comment Share on other sites More sharing options...
Vince Green Posted July 13, 2010 Report Share Posted July 13, 2010 (edited) You can try making a chamber cast using blue tack. Its a bit fiddly and nowhere near as accurate as a proper chamber cast using molten sulphur but it will give you some idea of what the rifling is doing. It could be that you have a very gentle "lead" (taper) into the rifling and you wont get the bullet to touch. Otherwise, the idea with a cleaning rod sounds good. Mark your bullets with a felt marker pen though, don't try to rely on feel. The other thing though is what other brands of ammo have you tried? It could also be that your rifle is fussy on ammo. The 7x57 is not known as a fussy calibre in general but you may get problems due to twist if you start trying heavier bullets. Edited July 13, 2010 by Vince Green Quote Link to comment Share on other sites More sharing options...
njc110381 Posted July 14, 2010 Author Report Share Posted July 14, 2010 From the bits of info I've been picking up from various places it seems that heavy bullets are common in this calibre. I think it may just be that it needs a bit more weight to work well. Quote Link to comment Share on other sites More sharing options...
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