30 BR Long Range report

[dtknowles]

I shot both my softer bullets and my linotype bullets again today. They are Lyman 31141 sized 0.310 and gas checked. Lubed with NRA 50/50. It was windy but I had my wind flags today. Groups with Linotype were no better than before but I did not change anything so that is no surprise. I was hoping for fewer fliers because I was more careful loading them, I think maybe it is a problem with my bench technique. These rounds have more recoil than my other bench rest guns. We are talking 172 gr. at 2000 fps. I am thinking of moving away from free recoil.

The softer bullets (COWW with 1% tin) shot better at this higher velocity but some still show a bit of keyholing.

I am not reporting the groups sizes as they are not much changed but they are mostly between 1.5 and 2 inches except the group with the wild flyer.



Tim

[charlie b]

I assume this is 100yd? What twist rifling do you have? Are you weight sorting your bullets? Do you have these same size groups, or groups with fliers, when shooting jacketed? Are you using Hornady gas checks? When the bullet is seated is the gas check below the neck, ie, inside the main portion of the case? Do your bullets have any base defects, or is the sprue projecting above the base of the bullet (upsetting the seating of the gas check)?

I am also assuming your reloading techniques are are consistent with your rifle and cartridge.

[dtknowles]

I assume this is 100yd? What twist rifling do you have? Are you weight sorting your bullets? Do you have these same size groups, or groups with fliers, when shooting jacketed? Are you using Hornady gas checks? When the bullet is seated is the gas check below the neck, ie, inside the main portion of the case? Do your bullets have any base defects, or is the sprue projecting above the base of the bullet (upsetting the seating of the gas check)?

I am also assuming your reloading techniques are are consistent with your rifle and cartridge.

Yes, 100 Yards. The twist is 1 in 14. I weight sorted the Lino bullets the ones I shoot for groups are within half a grain of each other and all that the visually good ones I cast were within a grain. This gun shoots bench rest 125 gr. jacketed bullets into less than half MOA, no fliers. Not great but Ok for this, I have a similar gun in 6mm PPC that shoots in the low 20's, less than a quarter MOA.

I was using Lyman gas checks but I ran out and switched to Hornady. That is a change from the last outing I failed to mention. I don't seat the bullets with the gas check below the neck but when I chamber the rounds the bullet gets pushed back into the case enough to push the gas check below the neck. I am setting up with low neck tension and shooting with the bullets jammed into the rifling.

Bullet bases are fine, sprues are cut clean. I really need a different mold. I had some XCB's a member sent me and I think I will get that mold. I shot the bullets he sent me with similar sized groups but I did not have things as well sorted then.

I am shooting neck sized, neck turned brass that is expanded in a bullet diameter M die. 0.310" I have tried 0.308 and 0.311 and 0.310 shot best back when I test diameters. I did not have a 0.309" sizer. I am weighing powder charges. My inline seating die is leaving marks on the bullets on the first driving band because of the large bullet diameter. I probably need to polish that a little.

Tim

[DDriller]

I would try loading them .005 and .010 off the lands. Pushing the bullet back with the rifling could be yoor flyer problem as they may not all be equal. Seating the gas check below the neck will not hurt.

[ascast]

I will be following your work/thread. very intertested

[charlie b]

Keep in mind that I also get fliers, probably one in 10 rounds. I attribute it to my bullet quality. I get better results when I use the heaviest bullets after sorting. I see a difference if sorted to 0.5gn batches or less.

I asked about Hornady checks because of the seating issue. If the checks are 'inside' the case you must use them or risk having a check come off (IMHO).

For your twist you can go a bit faster if it looks like that will perform better.

I would change your seating. I would bet you are having inconsistent seating depth. Choose to shoot with a jump or firmly jammed. If you choose to jam, then use firm neck tension. You don't want the bullet to move in the case. If you jump, then try some with a crimp and some without.

[dtknowles]

I will be following your work/thread. very intertested

Here is the tread with my earlier post.

http://castboolits.gunloads.com/show...h-cast-bullets

Tim

[dtknowles]

Keep in mind that I also get fliers, probably one in 10 rounds. I attribute it to my bullet quality. I get better results when I use the heaviest bullets after sorting. I see a difference if sorted to 0.5gn batches or less.

I asked about Hornady checks because of the seating issue. If the checks are 'inside' the case you must use them or risk having a check come off (IMHO).

For your twist you can go a bit faster if it looks like that will perform better.

I would change your seating. I would bet you are having inconsistent seating depth. Choose to shoot with a jump or firmly jammed. If you choose to jam, then use firm neck tension. You don't want the bullet to move in the case. If you jump, then try some with a crimp and some without.

Thanks Charlie. I will try some with the bullet seated to different distances off the lands. I don't think I can crimp with the dies I have, it is a bench rest inline seating die and when I tried it did not crimp.

I used the telescoping bullet technique with my 6mm PPC and that produced the best groups.

When I weight sorted the bullets I only get a couple that are on the heavy side almost all are in a half grain band with just a couple that are heavier and a few that are lighter the rest are in a half grain band. Out of 50 to 100 bullets I get only two that are heavy and like 10 that are light and like I said they are all within a grain band.

If I am going to up the velocity I am going to have to quit shooting free recoil. I think I need to anyway as even at this level it hurts and the gun is jumping too much on the bags. I have a foam pad on the stock. Originally the gun had just a flat aluminum plate.

My ability to adjust neck tension is limited. I probably need to get another neck sizing bushing. I have expanders in 310 and 308 so I can either change the case neck wall thickness by turning the brass or I can change the bullet diameter or I can have 2 thou of neck tension or none.

Tim

[charlie b]

OK, understand the limits of BR shooting dies. I would play with your available combinations to get a consistent case tension, even if you shoot with a jump.

I also get fewer of the 'heavy' bullets and more of the lighter. It is at least partly due to my technique with a bottom pour spout. If you 'hit' the edge of the sprue plate when pouring it can cause bad things in longer bullets, like voids (light bullets) and surface defects.

I find that free recoil and heavier bullets do not go together.

[Larry Gibson]

Here is the tread with my earlier post.

Tim

?????

[leadhead]

I shot a 308x1.5 which is almost the same as 30 BR. I think the only difference is the shoulder angle.
I shot the RCBS 165 gr cast bullet at pushing 2000 fps from a 1 in 10 twist Douglas barrel. It was
deadly accurate at 200 meters. I think I used 24.5 grs of 4895. The brass was cut down and resized
Winchester 308 brass. I shot many a 40x40 scores, and an 80x80 at the 1998 Internationals in Oak
Ridge in Tennessee.
Denny

[dtknowles]

?????

http://castboolits.gunloads.com/show...h-cast-bullets

I meant to post the link, don't know what went wrong. I fixed the post and added the link here. Thanks for point out the omission.

Tim

[dtknowles]

I shot a 308x1.5 which is almost the same as 30 BR. I think the only difference is the shoulder angle.
I shot the RCBS 165 gr cast bullet at pushing 2000 fps from a 1 in 10 twist Douglas barrel. It was
deadly accurate at 200 meters. I think I used 24.5 grs of 4895. The brass was cut down and resized
Winchester 308 brass. I shot many a 40x40 scores, and an 80x80 at the 1998 Internationals in Oak
Ridge in Tennessee.
Denny

I think you are talking about a pistol and metallic silhouettes? Short fat cartridges are supposed to be more accurate. My gun is 30 BR Long and is more like a 308 x 1.8. It is also a tight chamber and requires neck turned brass.

Tim

[leadhead]

OK Tim, Got it.... I've been out of the loop for many years and a lot of this stuff
has passed me by... It did bring back memories when I saw 30 BR. I still have a
set of 30 BR dies somewhere in the back of shelves. Sorry for the mix up.
Denny

[Larry Gibson]

dknowles

Thanks for posting the other thread. I just wanted the full story before offered anything. I also "got away from free recoil" technique of bench shooting with cast bullets. I found, even with a meticulously set up rifle on the "bags" that there is just too much recoil with the heavier cast bullets slower barrel time even at higher cast bullet velocity for consistent precision, just too many fliers and open groups when the "free recoil" method was used. I've learned to put my shoulder into the butt and pull straight back on the stock with the shooting hand. I don't "grip" the the stock in a traditional hold but curve/cup the non shooting fingers around the front of the grip and simply pull straight back. The non shooting hand then controls the rest adjustments and the rear bag. Takes a bit of practice to get it right but once you do it's comfortable and feels "natural".

I then, before shooting any rounds, settle into position and dry fire several times to get the feel of the set up. If something needs adjustment I becomes apparent right away because follow through on the dry fire shows in the reticle jumping way off the aiming point. When that happens it means I am compensating with muscular tension for a bad position. A good position allows, when the rifle is dry fired, for the reticle to just quiver on the aiming point. When I get a comfortable good position I now "know it" almost immediately. I found the more I used this technique the quicker it was to get the position right. I can now tell if the position is right with just one dry fire.

I never had that good of results with 3031 powder. "good" results yes but never the best results. I suggest you might try 4895, Varget or RL 15 [haven't tried RL 17 yet but it may be good also] if you have them in this time of critical shortage. BTW, the rifle and cartridge sound interesting and I'm looking for more results as you get them.

[dtknowles]

dknowles

Thanks for posting the other thread. I just wanted the full story before offered anything. I also "got away from free recoil" technique of bench shooting with cast bullets. I found, even with a meticulously set up rifle on the "bags" that there is just too much recoil with the heavier cast bullets slower barrel time even at higher cast bullet velocity for consistent precision, just too many fliers and open groups when the "free recoil" method was used. I've learned to put my shoulder into the butt and pull straight back on the stock with the shooting hand. I don't "grip" the the stock in a traditional hold but curve/cup the non shooting fingers around the front of the grip and simply pull straight back. The non shooting hand then controls the rest adjustments and the rear bag. Takes a bit of practice to get it right but once you do it's comfortable and feels "natural".

I then, before shooting any rounds, settle into position and dry fire several times to get the feel of the set up. If something needs adjustment I becomes apparent right away because follow through on the dry fire shows in the reticle jumping way off the aiming point. When that happens it means I am compensating with muscular tension for a bad position. A good position allows, when the rifle is dry fired, for the reticle to just quiver on the aiming point. When I get a comfortable good position I now "know it" almost immediately. I found the more I used this technique the quicker it was to get the position right. I can now tell if the position is right with just one dry fire.

I never had that good of results with 3031 powder. "good" results yes but never the best results. I suggest you might try 4895, Varget or RL 15 [haven't tried RL 17 yet but it may be good also] if you have them in this time of critical shortage. BTW, the rifle and cartridge sound interesting and I'm looking for more results as you get them.

Thanks for the bench rest tips and I have already switched powders to BLC2 and I will look thru my supplies to see if I have any 4895, I know I don't have the others. I do have Reloader 10X.

Tim

[dtknowles]

OK Tim, Got it.... I've been out of the loop for many years and a lot of this stuff
has passed me by... It did bring back memories when I saw 30 BR. I still have a
set of 30 BR dies somewhere in the back of shelves. Sorry for the mix up.
Denny

No problem, always glad to here about good things from other members.

Tim

[MT Chambers]

To see what works best in the .30 br. just look at the results in CBA benchrest matches as this is the darling of accuracy seeking cast boolit shooters ie: Saeco #315, Eagan MX4, MX3, (if you can find them), LBT spitzers (if you can get them to fit/chamber). Your twist rate is slow and may disqualify many of the favourite boolits with stability probs.

[dtknowles]

To see what works best in the .30 br. just look at the results in CBA benchrest matches as this is the darling of accuracy seeking cast boolit shooters ie: Saeco #315, Eagan MX4, MX3, (if you can find them), LBT spitzers (if you can get them to fit/chamber). Your twist rate is slow and may disqualify many of the favourite boolits with stability probs.

I think this rifle started out as a jacketed bullet shooter and they shoot lighter bullets.

This is from Accurate Shooter. https://www.accurateshooter.com/cartridge-guides/30br/

Bullet Weights and Profiles by Al Nyhus

30BRs work best with bullets not exceeding 125 grains. Jacket lengths should be either .925″ for the 110-112gr bullets or 1.00″ for the 118-125s. Ogives can be either 7 or 10 tangent ogives, but be aware that the shorter .925″ jackets require virtually no freebore length. The ‘zero freebore’ chambers can also be used with 1.00″ bullets. I currently use a .030″ freebore with the 1.00″-jacketed bullets and this works fine. Twist rates from 1:15 to 1:18 work well, with the edge going to the 1:17 and 1:18 versions at this point. A 1:15 twist rate allows use of the 125gr bullets built on 1.080″ jackets, but the freebore may be too long if you wish to change to the shorter 1.00″ bullets, especially if you prefer the 10-ogive models. I suggest setting your chamber and freebore up for the 1.00″-jacketed bullets, regardless of twist rate.

Tim

[MT Chambers]

you are absolutely right, jacketed bullets used are around 125 grs. and barrel twist is approx. 17"....I thought you were chasing cast boolit accuracy, something totally different