Barnes manual list 71.5 gr or R-15 as max with 300 gr. TSX bullet. At 71.5 gr...I chronoed an average at ~2490 fps with no pressure signs. Loaded some with 72 grs. Will shoot tonight.

Anyone else shoot over 71.5 gr or R-15 with 300 gr TSX bullets?

ledvm,

Exact reciple I used for my '09 trip with TSX's, 71.5 grns. Used slightly less RL-15 with the 300 grn banded solids for same POI at 100.

72 Gr of RL-15 under a 270 Gr Northfork soft. 2630 FPS, accurate load. No pressure signs.

quote:

Originally posted by iamgene:
ledvm,

Exact reciple I used for my '09 trip with TSX's, 71.5 grns. Used slightly less RL-15 with the 300 grn banded solids for same POI at 100.

Gene, Get to work.

I am trying.....when I get back we can validate these wild claims and shoot that nice 416 Rigby of yours!

quote:

Originally posted by iamgene:
ledvm,

Exact reciple I used for my '09 trip with TSX's, 71.5 grns. Used slightly less RL-15 with the 300 grn banded solids for same POI at 100.

At 71.5...both shoot to same POI in my rifle and pretty darn accurate. I was hoping for a consistent >2500 FPS. I know I am splitting hairs. Will give you the report on the 72 grs.

ledvm,

Sounds like you got a load. FYI-using a Lee factory crimp with WW Large Mag primers with R-P brass. Good luck!

Yes...just looking for someone else that has gone over 71.5 with 300 grain TSX. Just a half grain...so I don't expect problems.

ledvm,

The following is what I achieved across an Oehler 35 (80 F); Kimber 89; 375 H&H; 24"; Zeiss 3X9 conquest ; measured 12' from the muzzle (1st sky screen)
Hornady Brass
Fed 215M
300 TSX
RL 15

72 gr; Avg 2537 FPS 1" groups (5 shots) C to C; Hi 2554, lo 2522
73 gr; Avg 2571 FPS 1.5" groups (5 shots) C to C; Hi 2581. Lo 2562

No pressure signs with either load. Might add 10 FPS for corrected muzzle velocity.

EZ

Wow ... just to prove that all rifles are different, my load for 300 gr TSXs in an M70 SS Classic is 68.0 gr of RL-15 on new Remington brass w old silver WLR primers. Gave me ~1 MOA and 2604 fps.

Didn't think I needed to go more than 2600 fps.

mstarling,

I have a Mod 70 SS that I converted from 375 H&H to 375 Weatherby, It has a very fast barrel as well. Might be common to that gun???

EZ

EZ,

Could be ... I certainly didn't expect that. I do run check weights regularly so I thing the electronic balance is correct.

I think I ran loads up to 70 gr with it ... but accuracy had begun to deteriorate and I felt the additional velocity was not worthwhile.

quote:

Originally posted by eezridr:
ledvm,

The following is what I achieved across an Oehler 35 (80 F); Kimber 89; 375 H&H; 24"; Zeiss 3X9 conquest ; measured 12' from the muzzle (1st sky screen)
Hornady Brass
Fed 215M
300 TSX
RL 15

72 gr; Avg 2537 FPS 1" groups (5 shots) C to C; Hi 2554, lo 2522
73 gr; Avg 2571 FPS 1.5" groups (5 shots) C to C; Hi 2581. Lo 2562

No pressure signs with either load. Might add 10 FPS for corrected muzzle velocity.

EZ

Cool! I think 72 gr will put me at an average just over 2500 as well that is what my goal is...a 2525 FPS average.

Ok...I loaded and shot some 72 gr R-15 loads.

The vel did not change at all with either soft or solid...~2490! Isn't that surprizing???

Going to shoot some 73's.

If the velocity didnt change that tells me your over max already.

I loaded 71 grains R-15 with the Barnes 300 TSX in my Savage Guide Gun 20" barrel. I had the load written in my load book but couldnt find my velocity for it. I probably had it written down in the dies that I sold with the rifle. If I remember right it was 2400 something.

Found my notes on here in an old post.

68 Varget 300 TSX 2467,2479

71 R-15 300 TSX 2479,2488

76 H4350 300 TSX 2452

RL 15 is a little temp sensitive. Was it a little warmer outside during your first round with 71.5 gr?
I may ask some silly questions, but?
Brass the same?
OAL the same?
Crimped vs non crimped?
Lot of powder the same?

Any of these might effect the velocity with 1/2 gr of powder.

quote:

Originally posted by ledvm:
Ok...I loaded and shot some 72 gr R-15 loads.

The vel did not change at all with either soft or solid...~2490! Isn't that surprizing???

Going to shoot some 73's.

All meticulously consistent...even the temp...best I recall...at least >90 & <100

quote:

If the velocity didnt change that tells me your over max already.

You may be 100% correct!

My std. load is 70.2 grs. of RL-15 and max in my gun is 74.5 grs. it appears. However I get 2560 FPS in my gun with 72 grs, and that suits me.

Varget and IMR-4350 gets me 2600 plus FPS with much less powder compaction at about 85 to 90 percent load density, and cases last a long time..

I also use a lot of IMR-4064, at 2566 FPS at about 85% load density it's fast and super accurate. Probably my all time favorite.

The .375 is easy to load for. My gun has a 26 inch barrel.

Last night I visited with a guy that says he shoots 76 g of R-15 under 300 gr TSX bullets!

I am gonna try some at 73 gr of R-15 and see if vel stays at the same ~2490 suggesting I am maxed out.

69.5 gr. RL-15 = average 2,550 in my 1938 Winchester actioned Hoffman Arms.

quote:

Originally posted by Frostbit:
69.5 gr. RL-15 = average 2,550 in my 1938 Winchester actioned Hoffman Arms.

Mine must just have a slow barrel??? It is a decently accurate rifle...a 1" 100 yard gun. but 71 gr of R-15 gave me ~2490 fps at 12 ft and then 72 gr did not increase at all!

Was going to go up to 73 gr just for one test to see what happened. ~2490 is good enough...just wanted a ~2525 - 2550.

Like I posted 74.5 of RL-15 seemed max in my gun, but I get almost 2600 FPS with the 70.2 grs. I see no reason to shoot my 74.5 load as it didn't bring it up that much and I was using new brass, older brass can change a new brass max load to an ultra max load in my experience.

quote:

Like I posted 74.5 of RL-22 seemed max in my gun

Ray,

Did you mean R-15???

Most ACCURATE in my 25" pre 64 varies only from 69.5 Failsafe, 69.0 North Fork, 70.5 Woodleigh and 73.5 Barnes Solid all at about 3.59. All 300 grain and all RL 15. Did move higher up to 73 with each but accuracy was not as good as loads noted.

Lane,
Thanks for catching that. I went back and made the corrections.

OK...finally shot the 73 gr of R-15 loads...they were the ticket. They averaged ~2570 both TSX & Barnes FNS and shot to the exact same POI. Accuracy was also superb!

Question though???

71 g => ~2470 ~100F when shooting
72 g => ~2470 ~95F when shooting
73 g => ~2570 exactly 103F when shooting

All 3 sets used the exact same set of brass. All loads weighed on RCBS Chargemaster. All used CCI LRM primers. All crimped with LFC die.

Why did the 72 gr loads not change in a linear relationship like I expected???

Nobody smarter than me want to answer my question? Do y'all just think it was an error in chronography that day of the 72's??? In the name of learning...may go back and do another batch of 72's.

quote:

Originally posted by ledvm:
Nobody smarter than me want to answer my question? Do y'all just think it was an error in chronography that day of the 72's??? In the name of learning...may go back and do another batch of 72's.

Well I'm probably no smarter than you and I have no answer to your question but I can definitely say that more powder is not always more velocity. I was working up loads one day for my .338 Win Mag with IMR-4350 and shot a nice group with 70.5 grains of powder, next group was 71 grains, nice but slightly open and less velocity with more powder.
I can't explain it there it was, based on a 5 shot average.

On the .375 and Reloader 15 topic my Win Stainless Classic 24" barrel shoots 71 grains of RL-15 in Federal cases, CCI 250 primers and 300 grain TSX Barnes into .5" 3 shot groups and 10 shot average speed is 2603 fps.
I went up to 73.5 grains but the accuracy tapered off so I left it at 71 grains which was fast and accurate.

snellstrom,

could you help, please? i've got a 375 being worked up and am looking at a 300 gr TSX as a load. what does it mean to seat it .050 off the lands and how is it done? i've read this before about barnes but don't understand.

i also noted on a box of factory 300 TSXs that the velocity was 2470 at the muzzle and offered about 8 inches or so drop at 300 with a 200 yard zero and yielded over 2400 ft lbs which is impressive to me. have you caluclated the 300 yard drop with the added velocity?

thanks,

jeff

quote:

I can definitely say that more powder is not always more velocity. I was working up loads one day for my .338 Win Mag with IMR-4350 and shot a nice group with 70.5 grains of powder, next group was 71 grains, nice but slightly open and less velocity with more powder.
I can't explain it there it was, based on a 5 shot average.

My rifle did almost the exact same thing.

It shot a tight group with 71 gr at slightly above 2470 fsp. It shot a poorer group with 72 g and actually decreased a little below 2470. At 73 gr...very tight (best group ever) and big jump in vel up to ~2570...which was more than I was hoping for but great with it.

I just thought it was odd as I had never experienced that phenomenon before.

quote:

Originally posted by jsl3170:
snellstrom,

could you help, please? i've got a 375 being worked up and am looking at a 300 gr TSX as a load. what does it mean to seat it .050 off the lands and how is it done? i've read this before about barnes but don't understand.

i also noted on a box of factory 300 TSXs that the velocity was 2470 at the muzzle and offered about 8 inches or so drop at 300 with a 200 yard zero and yielded over 2400 ft lbs which is impressive to me. have you caluclated the 300 yard drop with the added velocity?

thanks,

jeff

Jeff,

Read Hot-Core's post in this thread. http://forums.accuratereloadin...=956107624#956107624

Or you can buy a Stoney Point gauge. The above works pretty good however.

One possible scenario; I have noted that firing out of a clean barrel typically produces less velocity. It typically takes me 4-5 shots after cleaning for my guns to "settle in" with consistant velocities and they are typically higher.
Could it be that you cleaned your barrel prior to the 72 gr charge? Perhaps not cleaned between the 72 to 73 gr charge?
Just a thought???

Global warming?
Solar flares?

quote:

Originally posted by ledvm:

quote:

I can definitely say that more powder is not always more velocity. I was working up loads one day for my .338 Win Mag with IMR-4350 and shot a nice group with 70.5 grains of powder, next group was 71 grains, nice but slightly open and less velocity with more powder.
I can't explain it there it was, based on a 5 shot average.

My rifle did almost the exact same thing.

It shot a tight group with 71 gr at slightly above 2470 fsp. It shot a poorer group with 72 g and actually decreased a little below 2470. At 73 gr...very tight (best group ever) and big jump in vel up to ~2570...which was more than I was hoping for but great with it.

I just thought it was odd as I had never experienced that phenomenon before.

It was clean when I started with 71 g. Have not cleaned it since.

quote:

Originally posted by jsl3170:
snellstrom,

could you help, please? i've got a 375 being worked up and am looking at a 300 gr TSX as a load. what does it mean to seat it .050 off the lands and how is it done? i've read this before about barnes but don't understand.

i also noted on a box of factory 300 TSXs that the velocity was 2470 at the muzzle and offered about 8 inches or so drop at 300 with a 200 yard zero and yielded over 2400 ft lbs which is impressive to me. have you caluclated the 300 yard drop with the added velocity?

thanks,

jeff

If your rifle is like mine you can't seat to Barnes recommendations off the lands, the overall will be too long for your magazine. I ended up saeating mine to the operable length of the magazine and left it there. I had previously worked loads "off the lands" but they were not to fit in the magazine so I had to start over.

My loads trajectory is as follows using Sierra 6 software and follows it pretty close in real life. 300 TSX ar 2600 fps.

+2.5" @100yards
+ .7" @200 yards
- 8" @ 300yards
-25" @ 400 yards
This makes for a very useful rifle with lots of "smack" downrange. That 300 grain bullet is a big piece of ordinance!
Good luck with yours.

RX 15 with 375 HH 71 gr and NF solids and softs = 1 ragged hole at over 2600 in my CZ