First Time out with new .260

[Mirage]

Finally got to take my .260 encore out. Was a year in the making getting the bbl., then wood and finishing it myself. It is a 15" heavy sporter taper with 2" wide forearm from Bullberry.

1st load (break in) 100 gr. sierra HP / 31 grains H4895. Best group after sighying in scope was app. .75".

Other loads consisted of 120 gr speer / 120 gr BT with RL15 / Varget. Groups best group was .75", upto 2".

It is the first time shooting a single shot handgun, observations:

1. noise is incredible! had to war plugs+ muffs. Scared others off @ range.

2. recoil was not bad, just differrent from what I'm used to (44 mag / 357).

3. definately takes much greater concentration holding on a target dot @ 100 yds, bad habits really stand out keeping a handgun steady @ 100 yds!

4. Got fatigued after app. 35 rounds. Until i get used to it I'll have to limit testing "hunting loads". I will go back though with some very light loads of H4895 and just work on sight picture / technique.


Any suggestions:

1. techniques to improve 100+ yd. skills (besides obvious good eyes, squeeze etc.)

2. anybody load / shoot .260. How would RL19 / H4350 be in 15" bbl. with 120 gr bullets?

Thanks, Mirage

[haroldclark]

Noise and recoil in the 260 Remington

The powders you have been using are well suited to a 15” barrel in the 260 Remington according to my software that calculates how much powder burns in the barrel.  If you can get 97 to 98% burn, the noise and muzzle blast will not be as severe.  I have studied “Barrel Burn” extensively in the past couple of years and the software program is very accurate.

The faster burning powders are more efficient in the short 15” barrel.  Example:  37.2 grains of H4895 behind a Sierra 120 grain Match king bullet will burn 97.6% of the powder in a 15” barrel and produce approximately 2436 fps.  The overall cartridge length is 2.80 inches.  The bullet is seated .43 inches into the case neck.

You mentioned Reloader 19 as a potential powder.  44 Grains of Rel 19 behind the SRA bullet seated to the same depth above will burn approximately 87% in a 15” barrel.  Do not stand in tall dry grass and shoot this load.  The muzzle blast will be considerably more than the H4895 loading and still only provide 2433 fps.

Let us consider using H4198 powder.  31.6 grains will burn 99.9% in the 15 incher and provide 2406 fps.  If you are going to be hunting with this gun, the target will not know the difference between 2406 and 2436 fps.  There will be little muzzle blast and noise.  There will be less felt recoil too.

Another consideration is 37.7 grains of H335 (great metering powder) with same bullet and OAL.  The load will produce 99.16 % burn.  In reality, I have tested this powder in a 15” 7mm BR with a 162-grain bullet.  Note the burn rate is 99%.

With 39.6 grains of BLC-2 you will get 98.33 % barrel burn and in reality less noise.  I don’t know why, but this occurs with the 7mm BR.  Technically, it should blast a bit more than the H335 loading above.   The velocity should be 2501 fps with 51462 psi pressure.  Maximum pressure is 60,190 psi.

Reloader 15 fares fairly well with 97.83 % barrel burn with 38.4 grains and the Sierra bullet and produce 2500 fps.  I have never used Reloader 15 and I don’t know the noise
characteristics, so I don’t know if a 97.8% burn will be loud.

IMR 4350 is way too slow for a 15” barrel.

All of the above loads are within the pressure limitations for this cartridge, but as always, start a couple of grains lower and check for pressure signs.

Harold Clark

[Mirage]

Very interesting info., kind of validates what I've been thinking. Where did you get this program?

Another point you made about loads. Fred Smith of Bullberry told me about his chambers how tight they are and always start @ minimum loads. He claims in many cases you hit max pressure @ or close to "starting loads".

In my loads I mentioned the Speer manual had start load @ 37 gr, max @39 gr. The Hogdgon manual had same bullet / powder @ 36 gr start, 39 gr max.  I started @ 36.0, went to 37.0 then 37.5.  I got noticible primer flattening @ 37.5 gr, some @ 37 gr. !  I will work my way back down between 36~37.  Fred was right about the tight chamber !

Thanks, Mirage

[Javelina]

Just a quick note to concur with Fred Smith's advice to be very cautious when loading for a chamber he says is cut at minimum dimensions.  I own and shoot Bulberry chambers quite a bit - when Fred says it's tight, believe him and back off when you're doing load development.  Stay safe!

Safe and good shooting to you!  

Javelina

[Mirage]

Thanks for the advice javelina. I'm convinced I need to get a chronograph, particularly with the .250 improved bbl. on the way. I would feel more comfortable being in the "ballpark" fps range as the manual loads (adjusted for bbl. length) regardles of the grains used.

Mirage

[haroldclark]

Flatening of Primers as a pressure sign.  Before you use that as a pressure test, first fireform all the testing brass.  If you use new or full lengh sized brass in your chamber you cannot depend upon the primer for info.  The reason is that the case that does not fill the chamber perfectly may allow the primer to start to back out of the pocket.  In doing so, it gets hammered and jammed back into the pocket with the completed explosion.  It will be flat for certain.  Neck size the brass for the next test and then you can tell if the primers are really flattening.  Also, you should be checking for stiffness in opening the TC and extracting the fired case for sticking.

While fireforming my 7-30 waters brass that are made from 30-30 cases, it will flatten the primers severely.

Have fun with your 260.  I would like to have one, myself.

Harold Clark

[Mirage]

Interesting haroldclark.

The flattened primers were on virgin brass. Second outing did not use the loads that flattened previously, I backed off. What I did notice is that app. 5 rounds did not allow the action to close. I had necked size only with lee collet die. I had marked the "high pressure cases" before the 2nd loading. Sure enough, the round that did not allow the action to close were the "high pressure" rounds. Apparently the brass did not spring back enough after 1st firing and were too tight in the shoulder !. Again, Fred warned me to full length resize.

I would like to continue using the lee collet (love it, lazy condition from .22 hornet). Any advice besides shooying moderate pressure loads ?

[KYODE]

mirage....fellow kentuckian  i'm about 1 1/2hr or so from ya. near ashland.
i'd say those that ya neck sized need the shoulder bumped back some. i full length only for break open actions. i try to resize the case until the case sticks out of a removed barrel a tad(couple thousandths less) than the barrel to frame gap. you can get that barrel to frame gap measurement by closing on feeler gauges. till it's hard to pull out but closes fine.
remove the barrel and see how much a fired case sticks out of the chamber. you can eyeball/feel with blade type feeler gauges. keep adjusting full length sizer down until the case sticks out the needed amount. this could be .002"-.004"...roughly therabouts. you do NOT want the case to go below flush with the end of the barrel neither. misfires can happen in either case. in your case, i'm assuming :shock:  :lol: the case may be too long from case head to shoulder........so much so that it will not allow the action to close, and lockup.
if your gun would happen to close, but not lockup fully, it may misfire.

bumping the shoulder back may fix that situation also.

[haroldclark]

Hello, Mirage and Kyode,
I am a fellow Kentuckian too.  Born in Mt. Vernon, lived in Lexington and Richmond. I went to Highschool in Richmond. Small world isn't it?  Now, I'm in California.

Fred Smith at Bullberry recommends that you full length size the Improved cases for the 7-30 Waters AI.  I have never owned an Improved anything, except 7mm TCUs and I have 5 of those.  If I keep the loading in a moderate to almost hot, I can neck size for about 2 or 3 reloadings and more.  After a fashion, they don't fit the chamber very well or as well as I like.

Kyode had some good data there.

On velocities:  I have a software probram that nearly matches actual chronographed velocities.  If the barrel length is given with the actual brand of bullet and powder, I can run your load and tell you very accurately what velocity you should be getting.  I have tested this many times and the software prediction is within 10 to 20 fps +or -.

Harold Clark

[haroldclark]

On of the main things I need too, is the Over All Length of the cartridge.  A slight change one way or the other in seating depth will affect the velocity immensely.

Harold

[Mirage]

great info guys~ thanks alot !

Haroldclark:

all use R-P case, 210M primers.

120 gr. ballistic tip 2.867" col

a. 36.5 gr RL15
b. 36.5 gr. varget


120 gr Speer hot cor 2.844" col

a. 35.5 gr. H4895
b. 36.5 gr. varget

Mirage

[haroldclark]

use R-P case, 210M primers.

120 gr. ballistic tip 2.867" col

a. 36.5 gr RL15   Velocity = 2370 fps  96.02% Powder burn in the barrel

b. 36.5 gr. varget  Velocity = 2367 fps  95.7% powder burn in the barrel


120 gr Speer hot cor 2.844" col

a. 35.5 gr. H4895  2312 fps  95.69% Powder burn in the barrel
b. 36.5 gr. varget  2331 fps  95.19% Powder burn in the barrel

My software doesn't take into account brass brand or primer.  However, I notice a great variation in velocity between brass brands and Winchester is the thinnest and will produce less velocity.  Military brass is thicker like Remington and will produce higher velocities than Winchester.  Never use mixed headstamps on brass.  I have noted that while shooting at 400 yards with IMI (Isreal brass) and switch to the same load with Winchester brass, the bullet will drop 2 feet or more. (With 2000 fps cast bullet)

I hope this helps you.

Harold

[haroldclark]

Note:  With a 24” barrel rifle the following velocities can be expected.


120 gr. ballistic tip 2.867" col

a. 36.5 gr RL15   Velocity = 2715 fps  96.02% Powder burn in the barrel

b. 36.5 gr. varget  Velocity = 2692 fps  98.11% powder burn in the barrel


120 gr Speer hot cor 2.844" col   Note:  with a 24” barrel rifle the following velocities can be expected.

a. 35.5 gr. H4895  2649 fps  99.41% Powder burn in the barrel
b. 36.5 gr. varget  2599 fps  98.37% Powder burn in the barrel

All of your loads are well within a safe pressure area.

Harold

[jhalcott]

I am thinking about using 100 grain hp's instead of 140 factory loads in my 260.The question is ,ARE THEY ENOUGH?.I shot both at a 7" stack of phone books taped together.At 50 yards ,I could not tell the difference in exit holes.The 100's are very accurate,but the 140's will go sub 1 inch.
No, they do NOT shoot close enough to use them interchangeably.

[Mirage]

hey guys.

Off to South Carolina for a week for a Plant poject. I'll be taking the .260 along with 36.5 gr RL15 underneath a 120 gr BT. First time out hunting with my Encore handgun. I hope to get in 1 full day + a couple of nights. Hope to put the rig to the test.  It will be new to me juggling the task of wearing ear protection hunting, hope the logistics work out.

Mirage