new to forum with a throating question...

[MagnumWheelMan]

So... another new guy... Hi... I'm Magnum... I regularly shoot, informally ) off a bench, occasionally using prone position on my personal 300 yard range... I'm wanting to try some longer range shooting, & I'm currently building my 1st dedicated long range rifle. I'm wanting something a bit different, so I chose the last rifle my father in law, & former shooting mentor )bought before he died 12-14 years ago... an unfired BRNO ZKK-600

my current mentor a retired tool & die guy, & life long rifle & handgun builder & I are building this project..., I'm trying to keep the costs 'reasonable' as I won't be able to use this rifle for it's intended 600-1200 yards, except before or after crops come out in my area, & I've never shot that far before, I might really suck at it ) I chose a Richards Microfit Tactical Thumbhole stock, & a Shielen 6.5 mm untapered barrel blank & a PPG chamber reamer in 6.5 X 284... my Lapua brass & 138 grain moly Scenars & Hornaday new dimension dies showed up the other day, & the chamber is now roughed out... while my builder buddy has built 1000's of rifles, he's not well known for building long range rifles, & we are curious as to the type of throating I should be doing on the chamber... any suggestions ???

I've linked a couple pics of the project / where we were at last week... I could really use some help with a 'competition type' throat suggestion... thanks

 

[expiper]

HI Mag. ...what is the FB on your reamer...or do you have a seperate throater that you can adjust the FB to whatever you like?????....if you can ...somewhere around .188' FB is very popular and works good tooo....Rick Begenski came up with that dim. for the Sierra 142's in that cal...it is just about perfect...however..you are using Lapua bullets..I have not used them in 6.5 cal...but,, the .30 cal and 6mm Lapua bullets that I have used require 'more' FB than their Sierra counterparts...so be ready to go a lil' deeper with your throater.....I wuld try .188 first...then lengthen the FB if and when necessary...Roger

 

[MagnumWheelMan]

Thanks for the reply... I'm realizing I might need to give more info... as I'm mostly a single shot shooter, I find I often load longer than SAMMI cartridge lengths... the dummy rounds I assembled, measure 3.158 in length... if possible I like to keep the bullet out of the body of the case, so my buddy is guessing that I'd need around .218 more freebore for my cartridge at that length... are 'the' 6.5 X 284 shooters leaving that additional .188 on a SAMMI length cartridge, so I'd need 'about' the .218 + the .188 ) ???

if the competitive shooters are getting better results seating deeper, I could seat deeper, I'm just using a long action reciever, so I have all the length I need in my magazine

again, any help anyone has would be greatly appreciated... thanks... Mag

 

[expiper]

What FB does your reamer have???...the total FB shuld be around .188...and only longer if the additional ammount is necessary to get the bullet shank or bearing surface above the neck/shoulder junction ..,the area of the dreded 'donut')....if you are throating with a throating reamer...be careful and dont go tooo far...try a bullet and if it is too short then go deeper....take your time ...and be shure we,me-you-gunsmith) are all on the same page....post a reamer drawing if you like ...we can discuss it...Roger

 

[MagnumWheelMan]

sorry... I'm more of a shooter than a builder, so I'm grasping to understand everything...

this is the reamer I got...

reamer

I assume the freebore is either on the reamer or the pilot, I'm not sure what he used as a pilot, but he makes all kinds of stuff to make stuff being an old 'tool & die guy' ) I'll have to see... I think he said there is currently no freebore, & I thought he was originally looking for a taper angle & length of taper or ???

 

[expiper]

Since it is a 'Kiff' PTG reamer ...the FB dimension and Neck Dia. should be stamped right on it....it is sometimes hard to read,but, look it over...it shuld say ....that will answer lots of your ????....hope this helps...Roger
PS,,if it is anywhere near .188 ..I wuld go with it...

 

[1shot]

My 6.5x284 reamer is a Hendrickson,sic)? and has .294 neck and .195 freebore. When I first saw it I nearly had a stroke, but now that I'm shooting it, I'd say it's real close. Given the fact that I shoot either 140 JLK's or 139 Lapua Scenars,.188 has got to be real close with the current selection of bullets available.
I hope this helps,
Lloyd

 

[MagnumWheelMan]

Thanks guys... I got the item code off the reamer PTG # 593088 hopefully there is some more detailed description of it on thier website... Midways site doesn't offer much info...

BTW... got the barrel tapered now, I like heavy barrels ), here's a pic of it set into the un-inletted stock...

 

[expiper]

Hey your almost 'there',,,use 4831 or 4350 and it shuld soot great.....Roger

 

[MagnumWheelMan]

'there'... is still a long ways off in the pic with the trigger group, you can see the threaded stainless pillars... they are goin to be threaded & epoxyed into the stock, then machined to precise fit between the trigger group & the action, then the action will be bedded after the pillars are set & machined... still not positive of what we want for a throat... but the rest of the work marches on...

the cartridge is a nice looker..