Nose diameter question - I know my nose

[260 Striker]

Posted this question on Cast Boolits so might as well ask here too. I cast some NOE 269 145 grain FN bullets and sized them .265 for my 260 Savage Striker. When I figured out the seating depth I found 2/3s of the bullets will be in the case with about 1/2 of the bullet below the neck. Loooonnnnng bullet and not good. Guess that block will find a new home.

Anyway, ordered a RCBS 6.5-140-SILH mould since it looks like my RCBS 7mm moulds which I know are bore riders. I plan to size the noses of the 6.5 bullets to .257 which will make them bore riders in my Striker. I was just wondering if anyone here has cast bullets from the RCBS 6.5 mould and if the noses are close to .257 or .258. I will be using linotype so mine will probably be a little bigger if you are using WWs.

Just curious if this new mould will allow me to shoot cast in my 260. My Striker is extremely accurate with jacketed bullets and would like to get a good cast load for it.

Thanks for any info you can provide.

Update 7/22/15 - My RCBS 6.5 SIHL mould arrived today and I had to rush out and cast some bullets to see how they will seat in my 260 Striker. Cast out of straight linotype and barely cooled the noses are .257 or maybe a half thou bigger. Might shrink some more as they age. I took one and nose sized in a .257 H&I die then figured my overall length using the rod method mentioned in this string. The base of the bullet will end up about 1/8" below the neck/shoulder junction which I can live with. Just need to size, lube and nose size some so I can try this weekend. Now to see if my wimp loads will stabilize these bullets out to 200 meters.

[high standard 40]

Why was the NOE too long? Have you done a chamber cast? The reason I ask is because I had to think "outside the box" to find a truly accurate load for my UAS XP100 7TCU. Common accepted practice is to load a particular cast bullet so that all lube grooves are below the case mouth. I have to load bullets for my stated XP with little more than just the gascheck in the case neck. I then dust the exposed lube with powdered mica to help "encase" and protect the exposed lube. Many will suggest sizing bullets to be .001" over groove diameter. I size mine so that the drive bands are a "slip fit" into the chamber throat and then seat the bullets out as far as the chamber throat will allow (thus my previously mentioned exposed lube). As far as the bullet nose diameter question, I think you will find that you can't rely on all shipped molds from any mass production supplier to have the same specs for every mold. Nose diameters can and will vary from different mold lots, as do bore diameters of barrels of the same caliber. My RCBS 7MM 145 mold delivers a bullet with a nose that measures .2785" which will not "bore ride" in any 7MM firearm that I own. And actually, I am glad that my bullets do come out "oversized". This allows me to size the nose of my bullets to fit my various 7MM barrels which do vary between the ones I own by as much as .001" from smallest to largest. I size the nose to be a slip fit into the rifling.

My XP100 that I refer to, when loaded with commonly accepted practices----bullet sized .285" and seated to an overall length so that it would chamber easily, provided accuracy on the order of 4" for five shots at 100 yards with a 6X scope....regardless of alloy type, powder charge, or lube (of which I tried multiple combinations). After considerable testing I have been able to achieve sub MOA accuracy in that gun with the same bullet. But conventional wisdom had to be abandoned. I size my drive bands to .2865" (the bore is .284")...... I size the bullet nose to .277"......I seat the bullets out to fill the chamber throat......I found Linotype was not needed, Hardball alloy served just fine........I use the exact same powder type and charge level as I did with jacketed bullets.......I get about 1850 fps with this combination and zero leading of the bore and as mentioned sub MOA accuracy when I do my part. Oh, and I use Felix lube.

I know all of what I do is beyond what many are willing to accept. And sometimes people can buy a certain mold for a certain gun and it will work just fine. It happens......but it can't be relied on. Sometime cast bullets just don't fit as they drop from the mold. You have to make them fit.

[260 Striker]

Never have done chamber casts. To figure seating depth with any bullet, any cartridge I take a rod that I have covered with masking tape and drop down the barrel till it hits the breech face with the gun cocked, make a mark on the rod, remove rod and bolt if bolt gun and drop bullet I want to use into chamber and tap with rod till bullet won't fall out. Then insert rod back into muzzle (same end first as before) and slowly let it rest on nose of bullet. Make another mark and then take calipers to measure distance between marks. This is max overall length if bullet was into rifling. I then subtract anywhere from .025 to maybe .050 from that measurement and that is my seating depth for that bullet. Works everytime. I did that with the NOE bullets that I had sized to .265 and when checking that overall length 2/3s of the bullet was in the case with about 1/2 below the neck. The NOE 140 is very long and sized .265 will size about 2/3s of the bullet. I suspect this mould was made for 6.5 Swedes and/or 6.5 Jap cartridges that typically use the long 160 grain bullets. I too size the noses of my RCBS 145 and 168 bullets using .277 and all the 7mm guns I have used them in allow me to seat them out far enough so the bases never went below the necks. I was hoping the NOE had a long enough ogive to allow me to seat it out but apparently not. The RCBS 6.5 140 has the same shape as the two 7mm moulds so I'm hoping it will be a bore rider like the 7mms. I took a .257 jacketed bullet and slipped it into the muzzle of my 260. Was a slight fit and I didn't want to force it so I'm hoping sizing the noses of the 6.5 140s with a .257 H&I will allow me to seat them no lower than the bottom of the neck. I guess my 260 Striker has a short throat but I have to seat some Nosler Custom Competition 140 jacketed bullets out so far there not much bullet in the neck. That bullet really has a long ogive. I've only had one other gun that shot great with jacketed but hated cast bullets. Maybe my Striker is the same way. Time will tell. Thanks for the info.

[ole95]

very useful infor here
I now know why Tdaddy said he would never shoot cast bullet there is no way he can do all that Deciphering
Nutcase no need to look no further your someone to write the cast bullet column lays right before your eyes

[high standard 40]

260 Striker,
The first step to developing an accurate cast bullet load for bottleneck cases is to know your chamber and bore dimensions. The chamber can be determined by a chamber cast by either using Cerrosafe or doing a "pound cast". The bore slug is very easy to do, just drive a soft lead bullet through the bore and measure it. The chamber is a little more involved but is not really difficult. Your post on the Boolit forum has a reply with a link that takes you to a detailed explanation of the process. If you choose to bypass these simple steps you are left with the trial and error method. The problems that then arise can be purchasing molds that are wrong from the start and trying endless combinations of alloy, sizing, seating depth, and powder selections. You can't approach loading accurate cast bullets using the same techniques that we all apply to jacketed bullet load development. Two different animals. The first and MOST important step is knowing the chamber and bore dimensions.

[260 Striker]

HS40, You are 100% correct with your comments about chamber casting. I enjoy casting bullets for my guns and have been more lucky than smart (no comment TD!!) when it comes to finding accurate loads that are minute of ram. I read the pound cast info on CB Forum and might try that with my 260 if I can't find a good load. My current goals are to find a cast bullet that is not too long so I can at least seat them to the bottom of the neck. There aren't too many 6.5 moulds that may work in my short throat gun. Loverin bullets are definitely out due to their long bore diameter design. Knowing your specific chamber dimensions is not really important if you cannot get a bullet to seat correctly in the first place. I have lots of jacketed bullets for my Striker so I'm good for many more IHMSA seasons but would like to shoot some cast eventually. My misses are cheaper with cast bullets and I like to see those big silver spots on targets that I hit!!!!!!

[ole95]

Tdaddy I have the up most respect for both of these gentlemen
But there again I have the up most respect for you as well

[high standard 40]

Tdaddy I have the up most respect for both of these gentlemen
But there again I have the up most respect for you as well

Thanks for the compliment...........I think!

[i26963]

Why was the NOE too long? Have you done a chamber cast? The reason I ask is because I had to think "outside the box" to find a truly accurate load for my UAS XP100 7TCU. Common accepted practice is to load a particular cast bullet so that all lube grooves are below the case mouth. I have to load bullets for my stated XP with little more than just the gascheck in the case neck. I then dust the exposed lube with powdered mica to help "encase" and protect the exposed lube. Many will suggest sizing bullets to be .001" over groove diameter. I size mine so that the drive bands are a "slip fit" into the chamber throat and then seat the bullets out as far as the chamber throat will allow (thus my previously mentioned exposed lube). As far as the bullet nose diameter question, I think you will find that you can't rely on all shipped molds from any mass production supplier to have the same specs for every mold. Nose diameters can and will vary from different mold lots, as do bore diameters of barrels of the same caliber. My RCBS 7MM 145 mold delivers a bullet with a nose that measures .2785" which will not "bore ride" in any 7MM firearm that I own. And actually, I am glad that my bullets do come out "oversized". This allows me to size the nose of my bullets to fit my various 7MM barrels which do vary between the ones I own by as much as .001" from smallest to largest. I size the nose to be a slip fit into the rifling.

My XP100 that I refer to, when loaded with commonly accepted practices----bullet sized .285" and seated to an overall length so that it would chamber easily, provided accuracy on the order of 4" for five shots at 100 yards with a 6X scope....regardless of alloy type, powder charge, or lube (of which I tried multiple combinations). After considerable testing I have been able to achieve sub MOA accuracy in that gun with the same bullet. But conventional wisdom had to be abandoned. I size my drive bands to .2865" (the bore is .284")...... I size the bullet nose to .277"......I seat the bullets out to fill the chamber throat......I found Linotype was not needed, Hardball alloy served just fine........I use the exact same powder type and charge level as I did with jacketed bullets.......I get about 1850 fps with this combination and zero leading of the bore and as mentioned sub MOA accuracy when I do my part. Oh, and I use Felix lube.

I know all of what I do is beyond what many are willing to accept. And sometimes people can buy a certain mold for a certain gun and it will work just fine. It happens......but it can't be relied on. Sometime cast bullets just don't fit as they drop from the mold. You have to make them fit.

Charlie
Could you describe a little about how much force is a “slip fit” in the bore?
Do you have to forcefully push or is it easily pushed in the bore?
Thanks
Melvin

[jmoore]

Charlie
Could you describe a little about how much force is a “slip fit” in the bore?
Do you have to forcefully push or is it easily pushed in the bore?
Thanks
Melvin

Until the official reply, what I did after learning all this was to size the noses until they could be inserted into the muzzle end with just "light" (i.e., no gorilla grip required!) finger pressure before tumble lubing. They will generally have rub marks from the lands, but that's about it.

I do a Lee Liquid Alox/One Step floor wax (no longer made) tumble lube, which means that I have to crimp the case mouths to ensure that the bullet extracts with the case if the round isn't fired as the noses get coated as well. Otherwise, all my procedures came from high standard 40!

It was good enough to do a 40/40 with 9/10 shoot off targets earlier this year. (Did miss one Turkey the next time, but I think that was operator error. Since then got distracted by the .223s.)