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View Full Version : Model 12 LRP 260 Remington - Pretty Short Throat



Steinmaster
06-19-2014, 08:46 PM
I have been trying to find the right hand load for my LRP. I'm using 123gr Nosler Custom Competition, Lapua brass, and CCI200 primers. I've tried ladder tests for the following powders with so-so groupings (not good enough for me for a precision rifle): RE15, H4350, and RE19. I'm now getting the best groupings (0.350 @ 100 yards) with IMR4064.

I finally got my modified case for the Hornady OAL gauge and found the 123gr Nolser's seated at recommended COAL of 2.800 is only .011 from the lands (measured from the ogive). This seems to be a pretty tight throat. Is this normal for the LRP? I haven't tried 139-142grain bullets yet. Anyone else have a LRP like this (throat depth) and what loads have you found best for 123gr bullets. I'm going to go with IMR4064 and play with the seating depth to see if I can tighten-up the groups.

troutmaster
06-19-2014, 09:44 PM
I have the same rifle but I don't think the LRP I have has a throat that short. I will see what my OAL is with the 130 gn Berger Vld I'm using I will also give you the length of my bullet so you can do the math. I do like the rifle but need to try some other powder and see if I can tighten up the groups a bit. Or try some different cOAL. Some times I get fed up with load development and want to start shooting out there.

Steinmaster
06-19-2014, 09:50 PM
I have the same rifle but I don't think the LRP I have has a throat that short. I will see what my OAL is with the 130 gn Berger Vld I'm using I will also give you the length of my bullet so you can do the math. I do like the rifle but need to try some other powder and see if I can tighten up the groups a bit. Or try some different cOAL. Some times I get fed up with load development and want to start shooting out there.

I'm fed up with load development. I already went through a box of 100 bullets and I'm not done yet. I must be missing something to make this easier. I guess when you have powder type, powder weight, brass, primers, bullets, and seating depth as variables, it makes for lots of shooting to find the perfect load.

troutmaster
06-19-2014, 10:13 PM
Ok got down to the basement. My coal touching the land with a 130 gn berger vld is 2.905 inches but that's with a different bullet than you are using. The Bergers are 1.335+\-.002 long. I have the hornady tools for measuring COAL but I use the 25 cal insert as I still haven't been able to get the 26 call insert yet.

Steinmaster
06-19-2014, 10:18 PM
OK. Mine is touching lands at 2.811 (123gr Nosler CC). That's a big difference. I wouldn't have expected that in a precision rifle, even if it is not a custom build. I guess that's why we have to workup reloads specific for each rifle. I'm really itching to order a custom build (TMR or CPR model) from Accurate Ordnance. I've heard great things about them.

troutmaster
06-19-2014, 10:38 PM
I'm fed up with load development. I already went through a box of 100 bullets and I'm not done yet. I must be missing something to make this easier. I guess when you have powder type, powder weight, brass, primers, bullets, and seating depth as variables, it makes for lots of shooting to find the perfect load.
I hear you. I started mixing it up these days. I load 20 or so rounds to blast at the long range gongs than I load a few to see if I can get a tighter group. I got fed up looking at the same pice of paper all morning. I have spent all lot of money trying to get .25 in groups and I don't even know if I'm a good enough of a shot to do that. Be nice to have someone that is a proven shooter to shoot my rifle.

Bach
06-19-2014, 11:44 PM
I have the same issue. I loaded 140 grain nosler comps at 2.8" COAL since I didnt have the modified case. Wasnt a very good idea. Ruined 10 pieces of new brass to loose primer pockets because of overpressure. After making the modified case and taking measurments it appears that for 140 grain noslers 2.270COAL = at the lands. So when I loaded them at 2.8" I was jamming them 0.030". I didnt get any pressure signs next time with same load but 0.020" off the lands
With Lapua 139g 2.830" COAL = at the lands. Still kinda short.

Jay Mackey
06-22-2014, 08:33 AM
140 gr. SMK (moly), 37.9 gr. Viht. N150, CCI 200, Lapua brass, About 0.010" off lands. This is the accuracy load from the Sierra book & it shoots 1/4 moa in one of my LRP's out to 600 yds. 140 gr. Berger VLD match (moly), 43 gr. H4350, CCI 200, Win. 7-08 brass, touching the lands. This load is hot but shoots 1/2 moa to a 1000 yds.

yobuck
06-22-2014, 09:27 AM
Try it the old fashion way before special tools existed. Take a partially seated bullet in an empty unprimed case and seat it the rest of the way with the bolt.
Then experiment with different seating depths from there. You can smoke the bullet with a match or use a sharpie to determine land contact, no tools required.
Do that with each different bullet and save the final version of each for future die settings. Also, if your looking for max performance from your gun, find it before
playing around with loads. Take 1 round loaded on the upper end of reccommended load for that powder/bullet combination. Then load 1 round in 1 gr increases
till you feel youve gone the limit. Shoot each of those rounds closly observing the rifle for sticky bolt. When that happens STOP, back up a half grain and work backwards
from there with load workup. You will have found max for that combination in that gun with very few shots.

BoilerUP
06-22-2014, 10:16 AM
123gr Nosler CCs have a long ogive and short nose compared to the 123/140 AMax, 140 HPBT, and the 130gr Berger VLD; this will result in a much shorter COAL to lands than other types of bullets.

Here are some measurements I took this morning, first number bullet OAL second number is Base to Ogive (measured on digital calipers with Hornady #5 Comparator insert)

123CC: 1.200, .707
123 AMAX: 1.235, .666
140 AMAX: 1.370, .755
140 HPBT: 1.332, .761
142 SMK: 1.358, .784
130 Berger VLD: 1.353, .671
130 Norma Golden: 1.378, .781

In my McGowen 260" barrel with .118 freebore, here are estimated cartridge base-to-ogive length to lands.

123 CC: 2.285
123 Amax: 2.275
140 Amax: 2.265
140 HPBT: 2.285
142 SMK: 2.285
130 VLD: 2.255

You can subtract the bullet BTO figures from the bullet OAL to get nose length; add nose length to the cartridge base-to-ogive length to lands to estimate COAL. In my barrel, that would put 123 CCs on the lands at 2.778" COAL.

RevM
06-22-2014, 11:14 AM
Sniper's Hide has some nifty sticky posts in their reloading section. This one about finding max OAL (http://forum.snipershide.com/snipers-hide-reloading/44357-hand-loading-long-range-3-finding-start-oal.html) for a particular bullet and barrel is particularly helpful.

Jamie
06-22-2014, 12:00 PM
I'm now getting the best groupings (0.350 @ 100 yards) with IMR4064..............

.....................I'm fed up with load development. I already went through a box of 100 bullets and I'm not done yet. I must be missing something to make this easier.


Maybe 1/3 MOA is all that factory rifle will do, but that is not bad by any custom rifle builders expectations. Not judging or throwing rocks, just asking questions, but what kinda accuracy are you expecting from this rifle?

I had a Remington that started off at 4" groups. When I finally found the right combination (800 rounds later) it printed those picture perfect clover leafs.

BoilerUP
06-22-2014, 12:04 PM
Maybe 1/3 MOA is all that factory rifle will do, but that is not bad by any custom rifle builders expectations.

Everybody shoots factory rifles the .2s on the interwebs..."if they do their part".

chukarmandoo
06-22-2014, 12:50 PM
Everybody shoots factory rifles the .2s on the interwebs..."if they do their part".

Very true, very true. Kind of like me at age 62 trying to find a cougar that doesn't use a walker! I hear younger people find them all the time. For me they're extinct just like small groups.

yobuck
06-22-2014, 01:19 PM
Everybody shoots factory rifles the .2s on the interwebs..."if they do their part".

All the way out to a 1000 yds yet. And that laying on my belly atop a cactus plant.
Another round here for my buddies barkeep, and have one for yourself also. lol

Bach
06-22-2014, 03:07 PM
For my LRP 260
Berger hybrid 140 grain - 2.282" @ the lands. 2.960 COAL
Lapua scenar 139 grain - 2.295" @ the lands. 2.832 COAL
Measured with Hornady comparator and #5-26 insert.